How long does valacyclovir last

How long does valacyclovir last DEFAULT

Valacyclovir, Oral Tablet

Highlights for valacyclovir

  1. Valacyclovir oral tablet is available as a brand-name drug and a generic drug. Brand name: Valtrex.
  2. Valacyclovir comes only as a tablet you take by mouth.
  3. Valacyclovir oral tablet is used to treat viral infections caused by a group of viruses called herpes simplex viruses. It’s used to treat cold sores (oral herpes), shingles, or chickenpox. It’s also used to treat or prevent flare-ups of genital herpes.

Important warnings

  • Blood disorders warning: For certain people, this drug can cause thrombocytopenic purpura (TTP) or hemolytic uremic syndrome (HUS). These conditions cause a severely low level of red blood cells and platelets in your body. TTP or HUS can result in death. You’re at risk of these problems if you’ve had a bone marrow or a kidney transplant. You’re also at risk if you have advanced HIV or AIDS.
  • Kidney failure warning: In some cases, this drug can cause your kidneys to stop working. This can occur if you’re on a high dose of this medication and have existing kidney problems. It can also occur if you’re taking other drugs that can harm your kidneys, if you’re not well hydrated, or if you’re over the age of 65 years.
  • Effects on the central nervous system warning: If you have kidney disease or use this drug at higher doses than your doctor prescribes, it can build up in your body. High levels of this drug can cause serious side effects that impact your brain. Symptoms can include hallucinations (seeing or hearing things that aren’t real) or delusions (believing things that aren’t true). They can also include agitation, confusion, or seizures. If you have any of these side effects, stop taking this drug. Call 911 right away or go to the nearest emergency room.

What is valacyclovir?

Valacyclovir is a prescription drug. It comes in the form of a tablet you take by mouth.

Valacyclovir is available as a brand-name drug called Valtrex. It’s also available as a generic drug. Generic drugs usually cost less than the brand-name version. In some cases, they may not be available in every strength or form as the brand-name drug.

This drug may be used as part of a combination therapy. This means you may need to take it with other medications.

Why it’s used

Valacyclovir is used to treat viral infections caused by a group of viruses called herpes simplex viruses. These infections include oral and genital herpes, shingles, and chickenpox.

  • Oral herpes causes cold sores. These are small, painful sores that you can get in or around your mouth. Cold sores can be spread by kissing or other physical contact with the infected area of the skin.
  • Genital herpes is a sexually transmitted disease. This means it’s spread through sexual contact. Symptoms include small, painful blisters on the genital area. You can spread genital herpes to your sexual partner even when you don’t have any symptoms. This drug is used to treat or prevent flare-ups of genital herpes in people with normal immune systems, or in people with HIV.
  • Shinglesis caused by the same virus that causes chickenpox (varicella zoster). Symptoms of shingles include small, painful blisters that appear on the skin. Shingles can occur in people who have already had chickenpox. It can also spread to people who have not had chickenpox before through contact with the infected skin.
  • Chickenpoxcauses an itchy rash of small, red bumps that can look like pimples or insect bites. The rash can spread almost anywhere on the body. Chickenpox can also cause flu-like symptoms, such as fever or tiredness. This drug is used to treat chickenpox in children ages 2 to18 years who have a normal immune system.

How it works

Valacyclovir belongs to a class of drugs called antiviral drugs. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

The herpes virus spreads in your body by creating more of its cells. Valacyclovir works by making it harder for the herpes virus to multiply (make more cells) in your body.

This drug does not cure herpes infections. The herpes virus may still live in your body after treatment. This means the infection may occur again at a later time even after the symptoms of the first infection are gone. However, this drug can help prevent such a re-infection at a later time.

Valacyclovir side effects

Valacyclovir oral tablet doesn’t cause drowsiness, but it can cause other side effects.

More common side effects

The more common side effects of valacyclovir can include:

  • headache
  • nausea
  • vomiting
  • dizziness
  • pain in your stomach area

If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

  • Kidney failure. Symptoms can include:
    • severe drowsiness
    • urinating less than usual
    • swelling in your legs, ankles, or feet
  • Unusual mood or behavior. Symptoms can include:
    • aggressive behavior
    • unsteady or shaky movements
    • confusion
    • hallucinations
    • seizures
    • coma

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.

Reducing your risk of spreading herpes

Using this medication daily may help lower the risk of spreading this disease to your sexual partner. However, you should not have sexual contact with your partner when you have any symptoms of an outbreak of genital herpes. Even if you use safer sex practices such as using a condom, you can still spread genital herpes. Talk with your doctor for more information about how to have safer sex.

Valacyclovir may interact with other medications

An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well. To help prevent interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking.

To find out how valacyclovir oral tablet might interact with something else you’re taking, talk to your doctor or pharmacist.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you’re taking.

Valacyclovir warnings

This drug comes with several warnings.

Allergy warning

This drug can cause a severe allergic reaction. Symptoms can include:

  • trouble breathing
  • swelling of your throat or tongue

If you develop these symptoms, call 911 or go to the nearest emergency room.

Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).

Warnings for people with certain health conditions

For people with kidney problems: Your kidneys clear this drug from your body. If you have kidney problems or a history of kidney disease, you may not be able to clear it from your body. This may increase the levels of the drug in your body and cause more side effects. This drug can also make your kidney function worse. To help prevent these problems, your doctor may prescribe a lower dosage of this drug for you.

For people with advanced HIV or a history of transplant: If you have advanced HIV or a history of bone marrow or kidney transplant, you may be at a higher risk of certain blood disorders. These conditions are called thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). They can result in severely low red blood cells and platelets in your body. TTP or HUS can cause death.

Warnings for other groups

For pregnant women: This drug is a category B pregnancy drug. That means two things:

  1. Research in animals has not shown a risk to the fetus when the mother takes the drug.
  2. There aren’t enough studies done in humans to show if the drug poses a risk to the fetus.

Talk to your doctor if you’re pregnant or planning to become pregnant. Animal studies do not always predict the way humans would respond. Therefore, this drug should only be used in pregnancy if clearly needed.

Call your doctor right away if you become pregnant while taking this drug.

For women who are breastfeeding: This drug may pass into breast milk and may cause side effects in a child who is breastfed. Talk to your doctor if you breastfeed your child. You may need to decide whether to stop breastfeeding or stop taking this medication.

For seniors: The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

For children: This drug has not been studied for use in treatment or prevention of herpes simplex virus (HSV) infection in newborn babies. The following are other age limitations for use of this drug:

  • Oral herpes (cold sores): This drug has been studied and approved for treatment of cold sores in children ages 12 years and older.
  • Genital herpes: This drug has not been studied or approved for treatment of genital herpes in children younger than 18 years.
  • Shingles: This drug has not been studied or approved for treatment of shingles in children younger than 18 years.
  • Chickenpox: This drug has been studied and approved for treatment of chickenpox in children 2 to 18 years of age. This drug has not been studied or approved for treatment in children younger than 2 years of age.

How to take valacyclovir

All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:

  • your age
  • the condition being treated
  • the severity of your condition
  • other medical conditions you have
  • how you react to the first dose

Drug forms and strengths

Generic: Valacyclovir

  • Form: oral tablet
  • Strengths: 500 mg, 1 g

Brand: Valtrex

  • Form: oral tablet
  • Strengths: 500 mg, 1 g

Dosage for oral herpes

Adult dosage (ages 18–64 years)

  • Typical dosage: 2 g, twice per day for 1 day, taken 12 hours apart.
  • Note: Treatment should be started at the first sign of cold sore symptoms.

Child dosage (ages 12–17 years)

  • Typical dosage: 2 g, twice per day for 1 day, taken 12 hours apart.
  • Note: This drug should be started at the first sign of cold sore symptoms.

Child dosage (ages 0–11 years)

  • This drug has not been studied or approved for treatment of oral herpes in children younger than 12 years.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for genital herpes

Adult dosage (ages 18–64 years)

  • First episode: 1 g, taken twice per day for 10 days. This drug works best if it’s started within 48 hours of when the first symptom appears.
  • Repeating episodes: 500 mg, taken twice per day for 3 days. Treatment should be started when the first symptom appears.
  • For preventing flare-ups in people with a normal immune system: 500 mg to 1 g, taken once per day.
  • For preventing flare-ups in people with HIV: 500 mg, taken twice per day.
  • For reducing the risk of transmission to a sexual partner: 500 mg, taken once per day.

Child dosage (ages 0–17 years)

This drug has not been studied for the treatment of genital herpes in children younger than 18 years.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for shingles

Adult dosage (ages 18–64 years)

  • Typical dosage: 1 g, taken three times per day for seven days.
  • Note: Treatment should be started when the first symptom appears. This drug works best if it’s started within 48 hours of the first sign of a rash on the skin.

Child dosage (ages 0–17 years)

This drug has not been studied for the treatment of shingles in children younger than 18 years.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for chickenpox

Adult dosage (ages 18–64 years)

  • Typical dosage: 1 g, taken 3 times per day for seven days.
  • Note: Treatment should be started when the first symptom appears. This drug works best if it’s started within 48 hours of the first sign of a rash on the skin.

Child dosage (ages 2–18 years)

  • Typical dosage: 20 mg per kilogram of the child’s body weight, taken 3 times per day for 5 days.
  • Maximum dosage: 1 g, taken 3 times per day.
  • Note: Treatment should be started at the earliest sign or symptom.

Child dosage (ages 0–1 year)

This drug has not been studied or approved for treatment of chickenpox in children younger than two years.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always speak with your doctor or pharmacist about dosages that are right for you.

Take as directed

Valacyclovir oral tablet is used for short-term treatment of oral herpes, genital herpes, shingles, or chickenpox. It’s used for long-term treatment to prevent genital herpes, and to treat genital herpes that recurs (comes back).

This drug comes with serious risks if you don’t take it as prescribed.

If you stop taking the drug suddenly or don’t take it at all: The symptoms of your viral infection may not get better, or may get worse.

If you miss doses or don’t take the drug on schedule: Your medication may not work as well or may stop working completely. If you’re taking this drug to prevent flare-ups of the infection, a certain amount needs to be in your body at all times. You should not stop taking this drug unless your doctor tells you to stop.

If you take too much: You could have dangerous levels of the drug in your body. Symptoms of an overdose of this drug can include more severe side effects, such as:

  • headache
  • nausea
  • tiredness
  • dizziness
  • diarrhea
  • constipation
  • weakness or lack of energy

If you think you’ve taken too much of this drug, call your doctor or seek guidance from the American Association of Poison Control Centers at 1-800-222-1222 or through their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

What to do if you miss a dose: Take your dose as soon as you remember. But if you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This could result in dangerous side effects.

How to tell if the drug is working: Your symptoms from the viral infection should improve.

Important considerations for taking valacyclovir

Keep these considerations in mind if your doctor prescribes valacyclovir for you.

General

  • You can take this drug with or without food. Taking it with food may help reduce any upset stomach.
  • Take this drug at the time(s) recommended by your doctor.

Storage

  • Store valacyclovir at room temperature between 59°F and 77°F (15°C and 25°C).
  • Keep this drug away from light.
  • Don’t store this medication in moist or damp areas, such as bathrooms.

Refills

A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.

Travel

When traveling with your medication:

  • Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
  • Don’t worry about airport X-ray machines. They can’t harm your medication.
  • You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled container with you.
  • Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.

Availability

Not every pharmacy stocks this drug. When filling your prescription, be sure to call ahead to make sure your pharmacy carries it.

Hidden costs

You may need to have blood tests during your treatment with this drug. The cost of these tests will depend on your insurance coverage.

Prior authorization

Many insurance companies require a prior authorization for this drug. This means your doctor will need to get approval from your insurance company before your insurance company will pay for the prescription.

Are there any alternatives?

There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

Sours: https://www.healthline.com/health/drugs/valacyclovir-oral-tablet

What to know about valacyclovir

We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Here’s our process.

Valacyclovir is a prescription drug available in oral tablet form. It is the generic version of the brand-name drug Valtrex. Doctors prescribe valacyclovir to treat infections caused by the herpes virus, including genital herpes.

Below, we take a closer look at this drug and outline how it differs from acyclovir. We also look at the drug’s side effects and warnings.

About the herpes virus

There are two types of the herpes simplex virus: HSV-1 and HSV-2.

HSV-1 is the cause of most cold sores, while HSV-2 is involved in most cases of genital herpes. However, both HSV-1 and HSV-2 can cause herpes infections in either location.

A person can contract an HSV-1 infection through oral-to-oral contact such as kissing. It is also to pass on the HSV-1 virus through oral-to-genital contact, which results in genital herpes. People are more contagious when they have a flare-up of the virus and have active sores.

People usually get the HSV-2 virus through sexual contact and can pass on an HSV-2 infection even if they do not have obvious symptoms. Condoms can the risk of passing on genital herpes, but this is not guaranteed.

Another form of herpes virus is called the herpes zoster virus, which is more commonly known as shingles. The varicella-zoster virus (VZV), which is also known as chickenpox, lays dormant in the body after the initial infection. In some people, the virus may .

A person can only become infected with shingles if they have previously had chickenpox. However, someone who has never had chickenpox can become infected with the virus through someone with shingles if they have direct contact with open sores.

Learn more about shingles and how it is spread here.

How valacyclovir is used? 

Valacyclovir is only available by prescription. It treats the following viral infections:

  • oral herpes or cold sores
  • genital herpes
  • varicella-zoster virus (VZV) or chickenpox
  • herpes zoster or shingles

This antiviral drug can also help reduce the risk of transmitting genital herpes to another person.

There is an ongoing study to look into valacyclovir’s potential use for treating mild Alzheimer’s disease in people with HSV-1 or HSV-2.

Side effects

Possible mild side effects of taking valacyclovir include:

  • headache
  • nausea and vomiting
  • upset stomach
  • dizziness

Uncommon side effects include:

  • painful menstruation
  • depression
  • joint pain
  • low blood cell counts

In some cases, individuals may experience severe side effects such as kidney failure and nervous system problems.

Warnings

There are some warnings that come with valacyclovir.

  • People with advanced human immunodeficiency virus (HIV) and those who have recently received a bone marrow or kidney transplant may be at risk for blood disorders such as thrombotic thrombocytopenic purpura (TTP) or hemolytic uremic syndrome (HUS).
  • Some people may experience central nervous system side effects, such as confusion and hallucinations. This side effect is more likely in older adults.
  • Valacyclovir may cause an allergic reaction in some people. If a person has an allergic reaction to valacyclovir, they should seek emergency medical care.
  • Valacyclovir can interact with certain medications. People should talk to their doctor about potential interactions with any drugs, herbs, vitamins, or supplements they are taking.

Valacyclovir vs. Acyclovir

Both valacyclovir and acyclovir treat viral herpes infections and both are equally effective. The table below shows some key differences.

Both of these generic medications are covered by most medical insurance plans. However, a person should check with their plan provider to confirm coverage.

Where to buy online

A person can only purchase valacyclovir with a prescription from a doctor, but there are many online pharmacies that offer fast and efficient ways to receive medications.

When ordering online, websites such as Roman require that a person do one of the following:

  • Already have a prescription to upload.
  • Complete a questionnaire on symptoms and provide visual identification for a medical professional to review.
  • Provide the contact details for their doctor, so the company can contact them to verify the prescription.

Some companies may have other rules that individuals must follow to receive their prescribed medication.

Some companies, such as Lemonaid, offer valacyclovir in a way that the U.S. Food and Drug Administration (FDA) has not approved, meaning that the way the company prescribes the medication is not how the label recommends. This is known as off-label use. A person should consider contacting their doctor before using medications in this way.

Difference between brand name and generic options

The between brand-name and generic drugs is the cost. Generic versions of drugs may also look different from their brand-name counterparts. Generic medicines have the same active ingredients as brand-name drugs and both types are FDA approved.

Once an initial patent for a drug expires, companies can begin selling generic forms. Because repeat clinical testing is not necessary for generic medications, they cost less.

The brand name for valacyclovir is Valtrex. Acyclovir, a similar antiviral, goes by the brand name Zovirax.

Summary

Valacyclovir is an effective antiviral treatment for chickenpox, shingles, oral herpes, and genital herpes. While the drug cannot cure genital herpes, it can help a person manage their symptoms. It can also reduce instances of transmission.

If a person suspects they have a viral herpes infection, they should see a doctor. With shingles, treatment is necessary to get rid of the infection and prevent complications.

Sours: https://www.medicalnewstoday.com/articles/valacyclovir
  1. Rental communities in boca raton
  2. 10 inch t bars dyna
  3. Xbox series x headset astro

Valacyclovir is a prodrug, meaning it converts into a different substance once it’s absorbed and metabolized in the body. In the case of valacyclovir, your body will convert it into the active drug acyclovir (or ACV) after it’s absorbed and metabolized.

Acyclovir is itself a powerful antiviral drug that’s highly effective in treating herpes. However, it’s less bioavailable than valacyclovir, meaning that a larger percentage of valacyclovir is absorbed per dose compared to a direct dose of acyclovir.

Because valacyclovir is a prodrug, it’s only active in your body for a short period of time after it’s taken. On its own, its half-life is approximately 30 minutes.

However, once valacyclovir has converted into acyclovir, it has a half-life of 2.5 to 3.3 hours in people with normal renal function.

This means that a single dose of valacyclovir, after conversion into acyclovir by your body, will reduce in concentration every 2.5 hours to 3.3 hours. 

cold sore medicine that works

Your outbreak doesnt stand a chance against an Rx option.

Valacyclovir Dosage Guidelines and Usage Periods

Like most antiviral medication, valacyclovir generally isn’t designed to be used as a “one off” treatment for HSV-1 or HSV-2. Instead, most dosage protocols recommend using valacyclovir over the course of several days (often as long as one week) to control a herpes outbreak.

Dosage guidelines for valacyclovir can vary based on the symptoms you’re treating. Generally, valacyclovir usage periods and dosages are more conservative for cold sores and chickenpox than for an initial herpes simplex virus infection.

Our valacyclovir dosages guide includes sample therapeutic protocols for cold sores, genital herpes, shingles, chickenpox and other common conditions that are treated using valacyclovir. And if you want to learn more about valacyclovir in general, check out our Valacyclovir 101 guide, which goes over all the nitty gritty—potential valacyclovir interactions, valacyclovir dosage, how it's used, what it's used to treat, where you can buy it, etc.

As always, the best approach to treating any viral infection, including HSV-1 and HSV-2, is to discuss your situation with your doctor and follow the advice they provide.

Sours: https://www.forhims.com/blog/how-long-is-valacyclovir-valtrex-in-your-system
What Can Herpes Do To Your Brain?

Herpes is not simply an infection. Too many people suffer silently, fearing to even reach out to their healthcare providers. There are few conditions where a person’s care is so dependent on their participation. Time must be dedicated to education and to formulating a plan that is under your control.

Medication is available—and it works extremely well—but how it is used and when it is used can never be more precisely applied than when a person uses the guidance of experts to craft a personalized plan.

With the education we provide below, you will be able to decide how best to utilize all the tools at your disposal. The key is to learn as much as you can and make informed decisions. The information below will help you gain a level of independence you may not have realized is possible.

Read carefully your healthcare professional’s personalized treatment plan and all the material provided. It may well provide some new information that will be helpful to you. Nothing is sugar coated because we feel you deserve the information you need to live your life the way you want. Read it all along with the package insert and the information in the Prescribers’ Digital Reference (PDR).

One important point is that if the medicine prescribed does not improve your condition (now or at any time), or if your symptoms at any point in the future are not completely typical of your usual outbreak, then you must be seen by a physician in person and checked for other conditions.

Lastly, the plan your personal doctor or nurse practitioner has provided is just the initial plan.

You may well choose a different one after reading more about other options or, in 6 months, your life circumstances may have changed and a different plan may suit you better. Just reach out to us.  

We are here to make your life better, not to give you more challenges in finding the care you need. And don’t forget, contact us if you need us.


Your doctor or nurse practitioner has reviewed your medical information and has prescribed valacyclovir 500 mg to treat genital herpes. Valacyclovir has been approved to treat genital herpes in several ways. It can be taken to lessen the severity of an initial outbreak, to abort outbreaks when someone feels telltale signs (the prodrome) that tells them an outbreak is about to happen, or to prevent outbreaks and reduce the risk of transmitting herpes by taking one pill every day.

Your doctor or nurse practitioner has written a prescription for valacyclovir to be used to limit outbreaks and reduce the risk of transmitting herpes by taking one pill every day. One of the most important advances in herpes treatment came with the knowledge that transmission from an infected person to their uninfected partner could be reduced by the use of daily valacyclovir.

Valacyclovir not only reduces the number of outbreaks a person experiences when using the medication every day but it reduces the number of days that someone sheds the virus asymptomatically (shedding of the herpes virus from normal skin when a person feels completely well).

Asymptomatic shedding is how most transmissions occur. Reducing asymptomatic shedding results in fewer uninfected partners catching herpes. If a condom is worn and the medication used, the chances are cut in half compared to using a condom alone. Fewer outbreaks and fewer episodes of asymptomatic shedding means fewer people become infected.

In one study that followed the course of 144 couples in which one partner was infected and the other not infected, transmission occurred in 14 couples. In 9 of those cases, the person who transmitted the disease was completely free of symptoms—no outbreak, not even a prodrome (a warning that an attack was coming). The other 5 transmissions happened when the person who was infected had a prodrome or developed lesions near the time the infection was transmitted. As noted, the key to preventing transmission isn’t just limiting outbreaks but reducing asymptomatic shedding. Valacyclovir, taken daily, reduces the number of outbreaks a person experiences and the number of days that someone sheds the virus asymptomatically.

To reduce the number of outbreaks an infected person experiences and to reduce the risk of transmission to an uninfected partner (by up to 50%), the PDR recommends the infected partner take valacyclovir 500 mg/day.

The study measured results “in monogamous, heterosexual relationships when combined with safer sex practices.” The data are strong but refer to patients with 9 or fewer outbreaks each year. Also, the study ran only for 8 months.


An important point
Herpes can be transmitted to a partner despite best efforts like using a condom and using antiviral suppression therapy. Patients should never engage in sex without a condom or when they have an outbreak or a prodrome. Also, as asymptomatic shedding is more common in the seven days following an outbreak, it is prudent to avoid sex during that period, as well.

The following information (Preventing future outbreaks and Other ways to use the medication) is relevant if at some point you decide to go off suppression therapy and choose to try to abort outbreaks and use suppression therapy in some specific situations only.

Preventing Future Outbreaks

If you are just trying to abort outbreaks, make a note of everything you think may have made you more susceptible to an outbreak. Was there more irritation to the area? Did anything affect your immunity like another infection (e.g., a cold) or did you change something in your lifestyle that could have weakened your immune system (e.g., lack of sleep, stress, increased alcohol consumption)? No change is too small to note.

This is important because it will help you maintain the patterns that make herpes less likely to appear. For you, it may be a lack of sleep over a few consecutive nights that spurs most outbreaks. It might be excessive sun exposure or too much alcohol consumption. It could happen only when you are sick or just run down. Whatever it might be, over time you may come to recognize the issues and make changes that reduce the frequency of outbreaks.

Other ways to use the medication

Some patients ask if they can take the medication to prevent an outbreak when they least want to have one. The classic examples are a bride or groom on their wedding day, when first engaging in sex with a new partner, or going on that long planned and much-needed vacation with your partner or spouse. You don’t need to be getting married or about to rendezvous for a much-anticipated tryst to want to prevent a herpes outbreak at particular times. It could be that an outbreak would be uncomfortable during the holidays or at any time you determine.

That is what we mean when we say you have control. At one point in life, a person may choose to abort outbreaks when they feel them coming on, at another point they might choose suppression therapy, but that may change, too. Circumstances change; only you will be able to know how your circumstances affect which option you choose. That is why learning all you can is so important. It gives you independence. Things change and how you choose to use valacyclovir may change.

One other fact is worth noting. You have been prescribed 30 pills of valacyclovir 500 mg every month. You should always have medication on hand, so renew your prescription well before you run out. As long as valacyclovir proves effective and you are free of significant side effects, you should never have to worry about having access to what you need.

You can always drop a note to your doctor or nurse practitioner, the pharmacist, or the care team with any questions, issues, or changes you want to consider. There is no “extra” visit charge or cost if you just want to ask questions and learn more about how you can manage your condition.

Lastly, if you would like to switch to intermittent therapy, you can always hold back on getting more valacyclovir delivered.

This may be a new situation for you but as long as the medication works without causing you difficulties of any sort, you are in control.    


A wealth of herpes information (oral and genital)

In the United States, genital herpes caused by HSV-2 (Herpes Simplex Virus Type 2) is extremely common and the most frequent cause of genital ulcer disease. Yet, the people who have symptoms represent the smallest number of people infected. In fact, 80% of the people who have genital herpes do not know it. That means for every person with symptoms who takes the step to be treated as you have, there are 4 people who are infected but totally unaware. 

Much of what we know about herpes is different from what people learned during the height of the “fear” an infection caused when no treatment was available.

That is what we must change. We want you to learn the facts about herpes so you do not become a victim of the myths. Also, only by understanding the disease will you be able to work with your doctor or nurse practitioner to craft the right treatment plan for you as your life evolves. What suits you today may not in 6 months or in 5 years. If you understand herpes, and how medications can work in different circumstances, you will be able to take control of your life in ways you might not have known were possible.

Lastly, if you read the next few pages carefully (though seemingly simply) you probably will know more helpful facts about herpes than many doctors.

What is herpes?

Herpes is a virus. The herpes virus can barely be considered alive. It is little more than a strand of DNA (deoxyribonucleic acid), the code of life, safely hidden inside a shell of protein. On its own, a herpes virus cannot reproduce or do much of anything—until it infects us. When the herpes virus comes in contact with areas that are receptive, like the genitals or mouth, the virus invades the epithelial cells (skin cells) in that region.

Then, the DNA of the herpes virus is released into the skin cell. At that point, it quite literally takes over.

It directs the cell to make more herpes virus and, when they have made enough copies to damage the cell so severely that it bursts, millions of the newly formed viruses are released infecting more cells, eventually causing an ulcer.

That is what people can see and feel, but a good deal more than that happens. While it is infecting skin cells and causing pain and ulcers, it also begins to attack the nerve cells in the same area. When the virus enters the nerve cell, it not only reproduces but it moves up the nerve to a bundle of nerves in the back called the sacral plexus. Once it is in the nerves, it is essentially protected from being attacked by the body’s immune system. Nerve cells can never be replaced.

That is why when nerves in the spine are damaged people become paralyzed. Since nerves cannot reproduce themselves easily, the body is careful not to bombard them with all the weapons it has to clear infections. All the inflammation that is caused by the battle to eliminate infections elsewhere would be disastrous if that occurred with nerves.

There is no sense clearing an infection if nerve cells that could never be replaced are destroyed in the process.

The herpes virus is essentially protected from an attack by our immune system as long as it hides out in the nerves of the sacral plexus when it affects the genitals, or the “dorsal root ganglion” (a cluster of nerves in the neck region of the spine) when it infects the mouth.

Unfortunately, that leaves the virus in a perfect position to sneak back out when the immune system is suppressed in any way. That is how the virus is able to cause recurrent infections, especially during times of stress, illness, or any condition or circumstance that makes our immune system less vigilant. We will discuss that in detail later.

How common are HSV-1 and HSV-2?

Worldwide (in 2012) nearly one half billion people were infected with HSV-2 between the ages of 15 and 49—and the number rises with age and the number of life partners. More women than men have herpes (14.8% versus 8% global prevalence, respectively). In the US, the number of people infected has been dropping, but the news isn’t all good. The percentage of people with a positive blood test for HSV-2 has declined. In people age 14 to 49, 21% were positive in the early 90s. By 2010, that number dropped to about 16%. Unfortunately, the improvement has been seen mostly in the white population “with stable rates in black populations, resulting in worsening racial disparities such that for every one white man, four black men are infected, with similar ratios for women.”

The reasons for this might be that access to information, education—and the medication that can reduce the risk of transmission—has not been made available to all equally.

In the United States, the prevalence of HSV-1, which accounts for the vast majority of oral herpes, has dropped 29% among 14–19 year olds, from approximately 42% to 30%, over the past 30 years. As a result, adolescents and young adults may experience their first exposure to HSV-1 with the initiation of sexual activity, including oral sex.

How can it be that some people do not have symptoms of oral herpes and of genital herpes?

It is vital to understand that 80% of people with an infection have no symptoms they recognize. For those who experience severe or frequent outbreaks, that is difficult to understand. There are multiple explanations.

The first one is related to how we physicians first described the disease.

Before there were elegant tests to culture herpes, or to test lesions for signs of herpes DNA, and before accurate blood tests out of the University of Seattle, herpes was described by doctors by what they saw—and only by what they saw. This meant that only people who had visible lesions (sores) were diagnosed and doctors thought that all those who had herpes had symptoms. It turns out that patients with severe disease were just the tip of the iceberg, but doctors didn’t realize that. Unfortunately, too many myths and outright falsehoods became “common knowledge.”

The fact is most people have an immune response that holds the disease at bay—in terms of causing symptoms, that is. They are still infected and, as we will learn later, still able to transmit the disease, but the symptoms either do not occur or are so subtle that they go unnoticed or undiagnosed. Herpes can cause such minor complaints that they are ignored.

Herpes can appear as little more than an irritation or tiny erosion. A lesion tucked away in the genital region can be so small that it cannot be seen without doing some major stretching before trying or using a magnifying lens. Or the sore is in a place that is completely inaccessible to viewing (e.g., the anus, the groin, the vagina, or hidden within a small skin fold).

Also, the symptoms may disappear so quickly that they are dismissed, or never seen in time by a doctor, or a doctor does not recognize how minor herpes can be even when seen in time. This is true of oral and genital herpes.

Nevertheless, the people who have what we call asymptomatic herpes can still transmit the disease. They can do this because they can still “shed” the virus from the skin even without having a sore or a symptom that they recognize as herpes. Asymptomatic shedding occurs from the mouth in those with oral herpes, from the anal and genital region in those with genital herpes, and even from tears in people who have had herpes of the eye. The section on asymptomatic shedding explains this in detail.


Clinical manifestations of Oral HSV infection

Classically, the oral symptoms are familiar to most people who either have had an outbreak or seen them in others. The initial symptoms are a sense of tingling or itching that can occur 24 hours before any lesions appear.

The first visible symptoms are redness, followed by the forming of a papule or elevation of the skin affected (usually on the very edge of the lips where they transition to the skin of the face). Then, the small roundish elevations become filled with fluid (a vesicle), which can burst and reveal a small ulcer or divet in the skin. This will be painful and ooze fluid and within just a few days heal, usually without a scar. These lesions do not form solely on the edge of the lip. They can form anywhere on the face, particularly a region between the nose and lips and out to the first fold on the cheek called the “nasolabial fold.”

The virus hides in the nerves in the back of the neck called the dorsal root ganglion. When HSV-1 reactivates and comes out of that nerve it can take a route other than to the edge of the lip. It can even cause an outbreak on the back of the neck but, most often, it is the lips where outbreaks will recur.

Oral symptoms can be more easily seen but often are not understood to be related to herpes. Minor irritations that disappear quickly might easily be dismissed as a simple cut or reaction to spicy food.

Other people might mistakenly consider unrelated irritations to be herpes on the mouth when they are not. For example, canker sores that occur inside the mouth and can recur just like herpes are sometimes misdiagnosed by patients and doctors alike as being due to the HSV-1 virus when, in reality, it is possibly an immune reaction and not an infection. The same sometimes occurs with irritation on the corners of the mouth, called angular cheilitis or perleche. This can be idiopathic, meaning it has no known cause, or can be due to the buildup of fluid at the corners of the mouth. It is a perfect spot to nurture growths of yeast or fungus (think Candida) and the irritation can even lead to small cuts and sores.

We always advise patients to confirm their diagnosis if recurrent oral lesions are completely unresponsive to herpes antiviral therapy.  

Clinical manifestations of Genital HSV infection

HSV-2 is the leading cause of genital ulcers in the United States and throughout the world. We know that because a very accurate test called a PCR test, which is far more sensitive than a culture, has found herpes in 60% of genital ulcers. Remember that most people with herpes found by blood testing have had no symptoms of herpes. What follows is a description of herpes as it appears in those who experience symptoms, in people who are seen by doctors with lesions.

First outbreak or primary outbreak

For patients who have symptoms, the first outbreak can be the worst. During primary infection, patients may experience multiple genital ulcers that can cover larger areas of skin. It can be on both sides of the groin and be quite painful. They often experience burning during urination in addition to the local pain. They can have fever, headaches, muscle and joint pain, and their lymph nodes in the groin can be swollen and painful as well. With no therapy, the lesions will clear and heal without scarring (typically) in about 21 days. Therapy can shorten that period significantly.

The reason an initial outbreak can be so severe is that there are no antibodies to herpes when the virus first enters the body, (though a prior history of herpes type 1 can give someone antibodies that work a little bit to fight herpes type 2 and may make an outbreak a bit less severe.)
An initial outbreak can be caused by Herpes 1 and in developed countries like the US, the most common cause of an initial attack of herpes is actually herpes 1. Most people do not realize that someone infected with oral herpes from type 1 can perform fellatio or cunnilingus on a partner and transmit herpes 1 from their mouth to their partner’s genitals. If you think about it, why not? The problem is that many people don’t know they have oral herpes. It may be easier to see but not many people remember the cold sore they had when they were 3. Also, while most people in the past acquired herpes on the mouth as a child when exchanging saliva with other children who were infected, that has not been happening with anywhere near the same frequency. The rate of infection with Herpes 1 is lower now than at any time in the past. In the United States, HSV-1 has dropped 29% among 14–19 year olds, from 42.6% to 30.1% over the last 3 decades.

That means that adolescents who engage in sex are more likely to be exposed to Herpes 1 for the first time when having oral or vaginal sex. Changes in sexual practices have also made the transmission more likely.

Fellatio (a “blow job”) and cunnilingus (“going down”) are much more frequently practiced at younger ages and with fewer restraints imposed by cultural or social forces. That has made herpes 1 the most common cause of first outbreaks in developed countries. Nevertheless, herpes 1 and herpes 2 on the genitals do not behave identically in terms of recurrences. Herpes 1 is more “at home” in the oral region and has developed ways to deal with that environment. When on the genitals, it can cause all the same symptoms and can still be transmitted, but it has a milder course than when herpes 2 infects the genitals. This is discussed more in the section on recurrences.

Understanding how herpes can remain in the body yet be kept at bay to some degree is pivotal. Herpes enters the sacral plexus of nerves during an initial infection. As discussed above, the virus remains safe from attack by antibodies and the immune system as long as it is tucked away in the nervous system. That little trick, entering the nervous system where it neither damages the nerves nor can be attacked, makes herpes a particularly stubborn infection. It can slide down the nerves that go from the sacral plexus to the skin and cause more outbreaks in the future. These are called recurrences.

Recurrences occur in a milder version than the initial outbreak because the body is not completely defenseless. It is the ongoing battle between the herpes virus’ ability to stay safe in the nervous system and the body’s ability to mount a defense with antibodies that determines if symptoms will appear or not. In most people, the battle is a stalemate in terms of symptoms. Most people never have an outbreak or, if they do, they are so mild they are not noticed. In terms of keeping herpes under such control that the virus never exits the nervous system and sheds from the skin, the battle definitely tilts in favor of the virus.

It is in the ways herpes remains active in those who are infected, and able to spread to those who are not, that makes herpes such a difficult infection to control in terms of preventing outbreaks and preventing transmission.

However, control is possible—and that is the key.

Recurrences

While the immune system for the vast majority of people makes recurrences far less severe than a primary outbreak, periodic recurrences occur in genital HSV infections. They are also quite different in character.

First, since herpes is in the nerves of the patient, as the virus becomes more active and begins to travel down the nerve to the skin, a person may get symptoms that tell them an outbreak on the skin is about to appear.

They may get leg pain, back pain, a tingling sensation, burning, or itching. They might notice less specific symptoms like increased urination, but symptoms like fever or muscle aches are much less common than with an initial outbreak. These symptoms collectively are known as a prodrome. It is very variable but patients begin to recognize their pattern, their unique prodrome.

The outbreaks themselves are much milder. They tend to occur on one side of the body, to cover a smaller area, and are less painful. Swelling of the lymph nodes is uncommon and all the symptoms resolve much more quickly, lasting just 3–5 days.

Because herpes lives in the sacral plexus and nerves from that accumulation of nerves can reach out not just to the skin where the infection first started but to any area the nerves can go, recurrent outbreaks are not limited to the initial region it entered the body. They can occur on the buttocks, the thigh, or anywhere in the anal and genital regions. Recurrences in areas other than the genitals (e.g., thigh) have a similar pattern to those that occur on the genitals.

Also, while herpes tends to improve over time, people can get outbreaks at any point that their immune system is challenged. This can happen when another illness occurs, with cancer or cancer treatments, or with such simple changes as life stress due to divorce, moving, changing jobs, or death of a family member as examples. Excessive friction, sunburns, exhaustion, poor sleep patterns can also deplete a person’s immune system. In fact, anything that makes you less healthy or is a challenge to the system can make an outbreak more likely to occur. Over time patients not only recognize their prodromes, but they also recognize the circumstances associated with an outbreak.

In terms of the frequency of recurrences, genital HSV-2 recurs far more often than genital HSV-1. In the first year after primary infection with genital HSV-2, patients average about 5 recurrences. That drops by approximately 2 outbreaks per year in the following year. In the first year after a genital HSV-1 infection, the recurrence rate is just 1.3 outbreaks/year. That drops to a mere .7 outbreaks/year in the second year.

Those statistics can be misleading, however. Some patients have no outbreaks and others can experience 9 or more outbreaks per year. It is incredibly variable.

Remember, these statistics are all about symptoms. People often wonder why someone who had symptoms or who knew they had herpes, and who had outbreaks, would have sex when they had an outbreak and could transmit the disease. The problem is that herpes is shed from the skin even when people who get outbreaks feel perfectly well. Also, even the people who have no history of herpes, but in whom we know herpes is present (by blood tests), shedding of the virus from the skin occurs silently and the potential to transmit the virus exists.

This is called asymptomatic shedding and occurs in anyone who has herpes—whether they have symptoms or not.

What is asymptomatic shedding?

When a genital herpes outbreak occurs, the virus can be cultured for about 11 days with an initial outbreak and for about 4 days with a recurrence. Yet, the question is whether the virus can be found on the skin even in between outbreaks.

As it turns out, the herpes virus becomes active and can be “shed” from the skin on days when patients who have recurrences of genital HSV-2 feel perfectly well and in people who have only a positive blood test for HSV-2 and have never had an outbreak. In a pivotal study, women with symptomatic genital herpes Type 2 collected cultures from the cervix, vulva, and the rectum every day for over 3 months. They kept track of their symptoms with a daily diary, as well.

Shedding occurred without symptoms on 2% of the days in women with HSV-2 genital herpes. They shed more frequently in the 7 days prior to or following an outbreak. Shedding lasted fewer days when they were free of an outbreak but still accounted for one-third of all the days they shed the virus.

But what is the case for the over 80% of HSV-2-seropositive persons in the United States who are not aware that they are infected with HSV-2? Using a very advanced test called PCR (Polymerase Chain Reaction), samples from patients who had herpes type 2 but who had never had symptoms were compared to patients with genital HSV-2 who had symptoms in terms of shedding the herpes virus. The patients who had a history of symptoms shed the virus when they had no symptoms on 13% of days while those who only had HSV-2 by blood testing shed on 9% of days.

What is interesting is that the amount of virus shed during when no symptoms were present was essentially the same in both groups.

The precise rate of genital HSV-1 shedding in between outbreaks is not known but it is suspected it is far less than genital HSV-2 herpes. One small study using cultures, and not the much more sensitive PCR test, found shedding on only 1 out of every 200 days. Unfortunately, we know that HSV-1 also sheds asymptomatically from the mouth and in developed countries like the US, it is responsible for most of the new infections of genital herpes.

Some things are associated with a risk for shedding and some things are not. With genital herpes, time of the month in relation to menstruation, sexual orientation, and sex were not. Having a history of prior outbreaks, especially a history of more than 8 outbreaks/year, and being Caucasian, are a risk for an increase in asymptomatic genital shedding, as well as an increase in overall shedding (symptomatic and asymptomatic shedding combined).

Duration of asymptomatic shedding

Another factor associated with asymptomatic shedding is how long a patient has had the infection. The first year after acquiring genital HSV is the most difficult symptomatically—and it makes sense that would be the year with the most shedding of the virus. In one study, the shedding rate declined from one-quarter of days in the first year to 13% in the years that followed; however, the rate never seems to drop to 0. Even in people with HSV-2 who had the disease for 20 years, shedding still occurred on more than 10% of days.  

Herpes transmission

It has become clear that people who have antibodies in their blood to Herpes Type 2 shed the virus from their skin whether they have a history of outbreaks or not. Basically, if someone has antibodies to herpes, they are capable of transmitting the disease. In one study that followed the course of 144 couples in which one partner was infected and the other not infected, transmission occurred in 14 couples. In 9 of those cases, the person who transmitted the disease was completely free of symptoms—no outbreak, not even a prodrome (a warning that an attack was coming).

The other 5 transmissions happened when the person who was infected had a prodrome or developed lesions near the time the infection was transmitted. This makes sense. Shedding of the virus frequently occurs within 7 days of an outbreak, either before or after.

In another study of a vaccine that was totally ineffective 155 people acquired herpes from their partner. Only 57 people who became infected had any symptoms of herpes. That means 99 people acquired the infection and only knew about it because they were in a study and had a very accurate blood test that confirmed the infection. This is consistent with what we know, which is that the disease is most often transmitted by asymptomatic shedding (when people have no symptoms) and that the people who become infected most will have no symptoms (yet will be capable of transmitting the disease).

Some Important Information about Safe Sex

Although genital herpes is not generally a dangerous disease, most people want to do what they can to decrease the risks of transmitting the virus to their partner(s). There are a few methods that can help.

Using condoms: Condoms decrease the risks of transmitting STDs and double as contraception.

Taking suppressive therapy: Using valacyclovir daily to manage genital herpes decreases both outbreaks and asymptomatic shedding.

Asymptomatic shedding is the cause of most transmissions of herpes.

Abstaining from sex around outbreaks: Shedding is more common 7 days before and 7 days after outbreaks. Abstaining from sex for 7 days after an outbreak can decrease the risk of transmitting the herpes virus. Of course, it’s also important to abstain during your prodrome and an outbreak.

Lastly, you and your partners should always inform each other about STDs. Honesty is an important part of any sexual relationship. With treatment and a few precautions, genital herpes is highly manageable and the risk of transmitting it to a partner can be reduced significantly.

Herpes and pregnancy

In terms of transmission, women with herpes are often concerned most about transmitting the infection to their child during childbirth. They wonder how they can protect their baby if they could be shedding the virus and not have any symptoms. They wonder if they should take medication to reduce shedding the herpes virus; they fear they might need a C-section or even ask for one “just to be safe.” It is true that subclinical genital HSV shedding at the time of labor and delivery can infect a neonate and cause neonatal herpes, or herpes of the newborn—but it is exceedingly rare.

In one study, only 202 women out of more than 40,000 women who had genital HSV cultures at delivery were shedding herpes. Only a quarter of them had lesions; the rest were shedding subclinically. Out of those 40,000 women, only 10 newborns became infected but they all acquired herpes from mothers who were shedding asymptomatically.

The worst cases of newborn herpes happen when a mother becomes infected at the end of pregnancy and has not yet developed antibodies to herpes, antibodies she can share with a baby while in the womb, antibodies that go a long way toward protecting the newborn as it travels the birth canal.  

Herpes on other parts of the body

Herpes Whitlow

Herpes can infect skin on other areas of the body other than the mouth and genitals. You have learned how once the virus enters the body through the genitals and finds a home in the sacral plexus, it can travel back down any nerve in that cluster of nerves and reach the skin on the buttock, thigh, anus, rectum, or anywhere in the region of the groin.

However, the virus can enter the body any place that it lands where the skin might be more receptive because of a cut or tiny opening. This has been seen on the fingers and when herpes occurs on the finger, it is called a whitlow. This was most often seen in the past in dentist and dental healthcare providers.   

Herpes of the eye

Herpes can infect the eye and is called Herpes Simplex Keratitis. It most often involves only one eye and affects the cornea. It can cause pain, redness of the eye, tearing, light sensitivity, and a feeling like there is grit in the eye. Unlike herpes elsewhere, topical antiviral therapy is the treatment that is most effective when an outbreak occurs. It is noteworthy that viral shedding occurs in tears even when patients have no symptoms and that treatment with valacyclovir decreases the number of recurrences just like it does for infections elsewhere.

Treatment

Treatments for herpes (oral and genital) have been available for decades. The first highly effective medication was acyclovir. It proved effective in shortening outbreaks and was a boon at a time when so little seemed to work. In those early days having anything that could shorten an outbreak and even prevent them changed how people saw the disease.
Acyclovir worked in a very targeted way against Herpes DNA. In reality, there isn’t much more to a virus than its DNA and the proteins that cover it. To affect the virus, it is nearly essential to attack its DNA and that is what acyclovir does. DNA is made up of four repeating chemicals called nucleosides. How they are put together in a sequence determines everything, and we mean everything. It is the code of life. So, anything that stops a virus from making more of its DNA stops the virus from making more of itself. Acyclovir is almost an identical copy of one of those nucleosides (Guanine) that makes the code of life—almost an identical copy. One small change to the part of DNA that makes a chain grow makes it so acyclovir can be placed in the growing line of code while lacking the small structure needed so the next piece of code can be added. The chain terminates. Acyclovir is known as a synthetic nucleoside analog.

One limitation was that acyclovir was limited in how much could be absorbed through the intestines. Only 20% of it was ever used by the body. This limitation was overcome by creating something called a prodrug of acyclovir. Since Acyclovir is so poorly absorbed through the gut a mechanism was sought that would allow acyclovir to cross the bowel and get into the bloodstream.

By adding the amino acid l-valine to acyclovir, valacyclovir is created. With that extra amino acid, valacyclovir can be absorbed much better than acyclovir. Once in the body, the amino acid, valine, is severed from the valacyclovir and acyclovir can do what it does but now much more effectively since so much more of it is in the bloodstream. Twice a day or even once a day valacyclovir works better than 3–5 times/day of acyclovir. Another drug, famciclovir, uses the same concept to help penciclovir enter the body.


There are any number of conditions where doctors will assure patients that no one knows their disease as the patient does. That is never truer than with herpes. Recurrences can be so subtle that patients can detect them even when clinicians may glance over them without noticing a thing. Most importantly, however, many patients learn to recognize the unique prodrome that warns them an outbreak may be coming. Patients can identify specific shifts in senses and feelings that seem trivial but are consistent signals that the virus is about to make itself known. It can be a dull ache in the back of the thigh, a small increase in the frequency of urination, an odd discomfort in the groin, a sensitivity of a particular patch of skin; it can be anything, but it is specific. While patients may not have prodromes or outbreaks, those living with herpes recurrences often can predict an outbreak with uncanny accuracy.

What follows is a general discussion of the different ways medication can be used with more specific dosing guidelines following the discussion.

Genital herpes

To treat or abort an outbreak when there are early symptoms (prodrome)

That kind of knowledge can allow some patients to use the medication to abort an outbreak. Whether oral or genital, people can take medication when their specific prodrome tells them an outbreak is on the horizon. The medication will stop an outbreak cold (often) and when it does not, it can shorten a milder outbreak than they might have had otherwise.

To prevent outbreaks when there are no symptoms but outbreaks are more likely

Patients also learn the life circumstances or behaviors that lead to more outbreaks. For some, a lack of sleep, increased alcohol, another illness, stress, too much sunlight, irritation, or anything, in fact, that can affect one’s immunity can spur an outbreak. That means that some patients can know not just when they feel an outbreak coming on but can know when they are more likely to have an outbreak due to their circumstances. They might be under stress, having more sex so more irritated, drinking a bit more than they should or missing sleep over an extended period. They will know that they should avoid those triggers and do their best to do so, but they also might want to take medication preventatively knowing they are more vulnerable at that time. Essentially they might take the medication for a week or two until the stress that is making them more susceptible to an outbreak has resolved.

To suppress outbreaks for an extended period

Another way patients can take the medication is when they know they absolutely would like to do all they can to reduce their chance of having an outbreak at a pivotal time. The classic example would be during a honeymoon but taking medication to suppress outbreaks on a daily basis can be prudent when going on vacation, starting a new job, in a new relationship, or at any time a patient feels it is how they want to approach their condition. And that’s the key.

How medication is used is completely in your hands. Learn everything you can and do not worry about using the medication in the way that suits you best. That may change as your circumstances change, or as the condition changes, or even as your mind changes.

To prevent transmission to an uninfected partner

One of the most important advances in herpes treatment came with the knowledge that transmission from an infected person to their uninfected partner could be reduced by the use of valacyclovir. Valacyclovir not only reduces the number of outbreaks a person experiences when using the medication every day but it reduces the number of days that someone sheds the virus asymptomatically. That results in fewer uninfected partners catching herpes. If a condom is worn and the medication used, the chances are reduced at least in half compared to using a condom alone.

Fewer outbreaks and fewer episodes of shedding means fewer people become infected.

Oral herpes

Abort an outbreak at the earliest sign or symptom (prodrome)

At that earliest sign, two tablets of valacyclovir 1000 mg for a total of 2000 mg is taken by mouth as the first dose. Then, 12 hours later, 2 tablets of 1000 mg of valacyclovir, for a total of 2000 mg, is taken as the second and final dose. The second dose can be taken sooner than 12 hours but never before 6 hours have passed. Adequate hydration makes sure the medicine is cleared through the kidneys as it should be.
The medication is only approved for two doses and there is no evidence in studies to advise the use of medication once lesions have appeared.


Treatment of initial genital outbreak

In patients with a first outbreak, the symptoms can be very severe. Multiple painful, genital ulcers can cover large areas of skin on both sides of the groin. They can experience burning during urination, fever, headaches, muscle and joint pain, and swollen, painful lymph nodes in the groin. With no therapy, the lesions will clear and heal without scarring (typically) in about 21 days. For such patients, treatment is vital and can shorten the outbreak and ease the symptoms significantly. For the treatment of an initial episode of herpes genitalis, the FDA recommends taking valacyclovir 1 gram (1000 mg) twice a day for 10 days starting at the first sign or symptom of lesions, preferably within 48 hours of onset. The “CDC recommends this same dose for 7 to 10 days; treatment may be extended if healing is not complete after 10 days.” For HIV-infected patients, they recommend 1 gram (1000 mg) every 12 hours for 5 to 14 days.

Treatment of herpes labialis (i.e., cold sores)

To abort an outbreak of herpes on the lips or mouth the recommendation is that the patient should take 2 grams (2000 mg) of valacyclovir at the first sign or symptom of lesions and a second dose 12 hours later. The second dose should not be taken within 6 hours of the first. Those are the only doses recommended but patients sometimes take another dose or two of just 1 gram if they continue to have symptoms, or if a mild outbreak follows.

The PDR states that for HIV-infected patients, 1 gram (1000 mg) be taken every 12 hours for 5 to 10 days. Despite what some patients do when having continued symptoms the PDR states, “there are no data supporting the effectiveness of beginning treatment after the development of clinical signs of a cold sore (e.g., papule, vesicle, or ulcer).”

Treatment of recurrent herpes genitalis, including HIV-infected patients

To treat a recurrent outbreak, the FDA recommends using 500 mg of valacyclovir twice daily for 3 days starting at the first sign or symptom of lesions—preferably within 24 hours of onset. The CDC recommendation is identical but adds in the choice of using valacyclovir 1 g (1000 mg) one time a day for 5 days. Valacyclovir 1 g taken every 12 hours for 5 to 14 days is recommended by the HIV guidelines. The PDR also states, “There are no data supporting the effectiveness of beginning treatment more than 24 hours after the onset of symptoms.”

Treatment with suppressive therapy

The PDR states that for suppressive therapy of recurrent herpes genitalis in all patients valacyclovir 1 gram (1000 mg) should be taken once daily.

However, “in patients with a history of fewer than 9 recurrences per year, 500 mg once daily may be given.” They note that “500 mg once daily regimen appears to be less effective than other regimens in patients with 10 or more episodes per year.”

The PDR continues, “Safety and efficacy of valacyclovir beyond 1 year have not been established. In HIV-infected patients, 500 mg by mouth twice daily. The safety and efficacy of therapy beyond 6 months have not been established.”

To prevent transmission to a partner

The PDR recommends the infected partner take valacyclovir 500 mg once a day to decrease the risk of transmission to the uninfected partner “in monogamous, heterosexual relationships when combined with safer sex practices.” The data are strong but refer to patients with 9 or fewer outbreaks each year. Studies also did not run for an extended period so the PDR also states, “The efficacy of reducing transmission beyond 8 months in discordant couples has not been established.” This means they can only vouch for the data for an 8 month period of time.

An important point

Being diagnosed with genital herpes means you have acquired a sexually transmitted infection. If you have been diagnosed with genital herpes, you should have been checked for other sexually transmitted infections when you were diagnosed, including but not limited to HIV and syphilis. If you have not been, you should be and this is highly recommended.

Herpes can be transmitted to a partner despite best efforts like using a condom and using antiviral suppression therapy. Patients should never engage in sex without a condom or when they have an outbreak or a prodrome. Also, as asymptomatic shedding is more common in the seven days following an outbreak it is prudent to avoid sex during that period, as well.

Herpes and the risk of HIV infection

HSV-2 infection puts a person at greater risk of acquiring HIV infection—as much as 2 to 3 times the risk of those without herpes. The reason is that herpes creates ulcers that can make it easier for HIV to enter the body but general inflammation of the genitals is also responsible for the increased vulnerability to the infection. In women and men with positive blood tests for herpes, specialized testing shows signs of inflammation on the cervixes of women and under the foreskin of men. The specialized test is the finding of CD4 T cells. This is probably the result of the body’s immune system constantly fighting the herpes virus and it is seen even when no outbreak is evident. Of note, some CD4 T cells have been shown in the lab to be more susceptible to HIV infection than skin samples tested under the same conditions. Moreover, CD4 T cells hang around in inflamed tissue long after outbreaks heal.

This is another reason why STD testing is always the rule when beginning a new sexual relationship and why, whether having an outbreak or not, a condom is essential.

HSV-2 infection in HIV-infected individuals

HIV infected persons who have genital ulcers due to herpes are more likely to transmit HIV, as HIV is shed from these ulcers. Herpes itself may behave identically in the HIV positive individual but they are more likely to develop acyclovir resistance and to have outbreaks that last longer and appear different from typical cases.

HIV positivity is a complex condition that requires careful evaluation by experts in the field.

HSV vaccines

After years of frustration, there are reasons to be optimistic that a vaccine to prevent, or even to treat, herpes may be achievable. The development of a vaccine has been spurred by the realization that controlling herpes would be a major step in controlling the spread of herpes around the world, especially in places where medication is unavailable.

Herpevac vaccine did not prevent the acquisition of genital herpes Type 2 but it did show moderate success against catching herpes Type 1 and in making the disease milder if someone caught it. The study included 8000 participants but they were all women so the data may not be consistent in men. Nevertheless, the fact that a vaccine worked for HSV-1 is encouraging, especially since so many new cases of genital herpes are due to HSV-1. A number of vaccines are being tested to see if they could reduce the number of outbreaks and, most importantly, the amount of asymptomatic shedding. One vaccine in early testing, GEN-003, reduced shedding by 55%.

The advances are being made that give hope to anyone who has the infection or is the partner of someone with the HSV virus.


Read full prescribing information Here

How can Valtrex be used

Treatment of herpes labialis (i.e., cold sores)

To abort an outbreak of herpes on the lips or mouth the recommendation is that the patient should take 2 grams of Valacyclovir at the first sign or symptom of lesions and a second dose 12 hours later. The second dose should not be taken within 6 hours of the first. Those are the only doses recommended but patients sometimes take another dose or two of just 1 gram if they continue to have symptoms, or if a mild outbreak follows.

The PDR states that for HIV-infected patients, 1 gram (1000 mg) be taken every 12 hours for 5 to 10 days. Despite what some patients do when having continued symptoms the PDR states, “there are no data supporting the effectiveness of beginning treatment after the development of clinical signs of a cold sore (e.g., papule, vesicle, or ulcer).”

Treatment of Initial genital outbreak

In patients with a first outbreak, the symptoms can be very severe.

Multiple painful, genital ulcers can cover large areas of skin on both sides of the groin. They can experience burning during urination, fever, headaches, muscle and joint pain, and swollen, painful lymph nodes in the groin. With no therapy, the lesions will clear and heal without scarring (typically) in about 21 days. For such patients, treatment is vital and can shorten the outbreak and ease the symptoms significantly.

For the treatment of an initial episode of herpes genitalis, the FDA recommends taking valacyclovir 1 gram (1000 mg) twice a day for 10 days starting at the first sign or symptom of lesions, preferably within 48 hours of onset. The “CDC recommends this same dose for 7 to 10 days; treatment may be extended if healing is not complete after 10 days.”

For HIV-infected patients, they recommend 1 gram (1000 mg) every 12 hours for 5 to 14 days. The PDR also notes, “The efficacy of treatment with VALTREX, when initiated more than 72 hours after the onset of signs and symptoms, has not been established.”

Treatment of Recurrent Herpes Genitalis, Including HIV-infected Patients

To treat a recurrent outbreak, the FDA recommends using 500 mg of Valacyclovir twice daily for 3 days starting at the first sign or symptom of lesions—preferably within 24 hours of onset. The CDC recommendation is identical but adds in the choice of using Valacyclovir 1 gram (1000 mg) one time a day for 5 days. Valacyclovir 1 gram taken every 12 hours for 5 to 14 days is recommended by the HIV guidelines. The PDR also states, “There are no data supporting the effectiveness of beginning treatment more than 24 hours after the onset of symptoms.”

Treatment with Suppressive Therapy

The PDR states that for suppressive therapy of recurrent herpes genitalis in all patients Valacyclovir 1 gram (1000 mg) should be taken once daily.

However, “in patients with a history of fewer than 9 recurrences per year, 500 mg once daily may be given.” They note that “500 mg once daily regimen appears to be less effective than other regimens in patients with 10 or more episodes per year.”

The PDR continues, “Safety and efficacy of valacyclovir beyond 1 year have not been established. In HIV-infected patients, 500 mg PO twice daily. The safety and efficacy of therapy beyond 6 months have not been established.”

To Prevent Transmission to a Partner

The PDR recommends the infected partner take Valacyclovir 500 mg once a day to decrease the risk of transmission to the uninfected partner “in monogamous, heterosexual relationships when combined with safer sex practices.” The data are strong but refer to patients with 9 or fewer outbreaks each year. Studies also did not run for an extended period so the PDR also states, “The efficacy of reducing transmission beyond 8 months in discordant couples has not been established.” This means they can only vouch for the data for an 8 month period of time. The PDR also states, “The efficacy of VALTREX for the reduction of transmission of genital herpes in individuals with multiple partners and non-heterosexual couples has not been established. Safer sex practices should be used with suppressive therapy.” Centers for Disease Control 26 and Prevention [CDC] Sexually Transmitted Diseases Treatment Guidelines

Maximum Dose

In children 12 years and older, adolescents, adults, and the elderly, the maximum daily dose is 4 grams if given for just 1 day and 3 grams/day if given for more than 1 day.

In children 2 years to 11 years, 3 grams/day is the maximum dose.
Safety has not been established in neonates, infants, and children less than 2 years.

Dose adjustments should be made for those with kidney impairment or issues. Decreased doses are needed as kidney impairment slows the clearing from the body of valacyclovir. The degree of impairment determines the decrease in the dosage. The elderly may have decreased kidney function and adjustments should be considered in such cases.

No adjustment is needed, generally, in patients with liver impairment.

However, if you have a liver condition or impairment, inform your doctor.

Overdose: Valtrex is not usually harmful unless you take too much for several days. An excess of Valtrex can cause vomiting, kidney problems, confusion, agitation, feeling less aware, seeing things that aren’t there, or loss of consciousness. For severe symptoms, go direction to an emergency room. Otherwise, talk to your doctor or pharmacist if you take too much Valtrex. Take the medicine pack with you.


Sensitivity or Allergies: Patients with sensitivity or an allergy to any of the following medications should not use Valacyclovir: Acyclovir, Famciclovir, ganciclovir, penciclovir, valacyclovir, or valganciclovir.

Kidney Issues: Dose adjustments should be made for those with kidney impairment or issues. Decreased doses are needed as kidney impairment slows the clearing from the body of valacyclovir. The degree of impairment determines the decrease in the dosage. The PDR states, “Acute renal failure and CNS (Nervous System) toxicity have been reported in patients with underlying renal (Kidney) dysfunction who have received inappropriately high doses of valacyclovir for their level of renal (Kidney) function. Patients receiving potentially nephrotoxic(Toxic to the Kidney) drugs together with valacyclovir may have an increased risk of renal dysfunction (impairment).”

The Elderly: The elderly are more likely to have impaired kidneys so they might not clear valacyclovir from their system as efficiently as they should. This can lead to inappropriately high levels of valacyclovir, which means the elderly may need lower doses of valacyclovir. The elderly are also more likely to experience neurological side effects, including: agitation, hallucinations, confusion, delirium, and other abnormalities of brain function termed encephalopathy.

Dehydration: When patients are dehydrated acyclovir can reform as a solid in the kidney leading to kidney damage. Patients should all remain well hydrated when taking valacyclovir.

Newborns, Infants, and children: Safety has not been established in neonates, infants, and children less than 2 years.

Pregnancy: While a registry that collected data on the 756 pregnancies of women exposed to acyclovir in the first trimester showed no greater occurrence of birth defects than occurs in the general population, the study size was too small to guarantee safety during pregnancy.

You should not take valacyclovir if you are pregnant or trying to become pregnant, unless recommended by your obstetrician/gynecologist or other healthcare provider.

Breastfeeding: The PDR states, “According to the manufacturer, valacyclovir should be administered to a nursing mother with caution and only when indicated. Although the American Academy of Pediatrics (AAP) has not specifically evaluated valacyclovir, systemic maternal acyclovir is considered to be usually compatible with breastfeeding…Consider the benefits of breastfeeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition.”

Driving or Using Machines: Valtrex can cause side effects that affect your ability to drive. Don’t drive or use machines unless you are sure you’re not affected.

Thrombotic Thrombocytopenic Purpura/Hemolytic Uremic Syndrome (TTP/HUS): TTP/HUS is a rare condition but has occurred in patients with advanced HIV disease and also in allogeneic bone marrow transplant and renal transplant recipients participating in clinical trials of VALTREX at doses of 8 grams per day. If any of these conditions apply to you, please inform your doctor and pharmacist.


What follows is a summary and does not include every side effect possible. Please, read the package insert and report any side effects you experience whether on the list below or not.

Very Common (may affect more than 1 in 10 people): headache

Common (may affect up to 1 in 10 people): feeling sick, dizziness, vomiting, diarrhea, skin reaction after exposure to sunlight (photosensitivity), rash, itching (pruritus)

Uncommon (may affect up to 1 in 100 people), feeling confused, seeing or hearing things that aren’t there (hallucinations), feeling very drowsy, tremors, feeling agitated

These nervous system side effects usually occur in people with kidney problems, the elderly or in organ transplant patients taking high doses of 8 grams or more of Valtrex a day. They usually get better when Valtrex is stopped or the dose reduced.

Other Uncommon Side Effects: shortness of breath (dyspnea), stomach discomfort, rash, sometimes itchy, hive-like rash (urticaria), low back pain (kidney pain), blood in the urine (hematuria)

Uncommon Side Effects That May Show Up In Blood Tests: reduction in the number of blood platelets which are cells that help blood to clot (thrombocytopenia), reduction in the number of white blood cells (leukopenia), increase in substances produced by the liver  

Rare (may affect up to 1 in 1,000 people): unsteadiness when walking and lack of coordination (ataxia), slow, slurred speech (dysarthria), fits (convulsions), altered brain function (encephalopathy), unconsciousness (coma), confused or disturbed thoughts (delirium)

These nervous system side effects usually occur in people with kidney problems, the elderly or in organ transplant patients taking high doses of 8 grams or more of Valtrex a day. They usually get better when Valtrex is stopped or the dose reduced.

Other Rare Side Effects: kidney problems where you pass little or no urine.

Lastly, watch out for a severe allergy. It may be rare but it can be life-threatening so being aware of the symptoms is vital.

Severe allergic reactions (anaphylaxis): These are rare in people taking Valtrex. Anaphylaxis is marked by the rapid development of flushing, itchy skin rash, swelling of the lips, face, neck, and throat—causing difficulty in breathing (angioedema), fall in blood pressure leading to collapse. If any of these occur, get emergency treatment immediately


Of Note: “When Valtrex is coadministered with antacids, cimetidine and/or probenecid, digoxin, or thiazide diuretics in patients with normal renal function, the effects are not considered to be of clinical significance. Therefore, when VALTREX is coadministered with these drugs in patients with normal renal function, no dosage adjustment is recommended.” (PDR)

Aprotinin: Aprotinin is cleared in the kidney as is Valacyclovir. Together, the risk to the kidney is increased.

Bictegravir; Emtricitabine; Tenofovir Alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.  

Cimetidine: Cimetidine may slow how quickly valacyclovir is cleared out of the body through the kidney but no dosage adjustments are recommended for patients with normal renal function.

Cobicistat; Elvitegravir; Emtricitabine; Tenofovir
Alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Cobicistat; Elvitegravir; Emtricitabine; Tenofovir Disoproxil Fumarate: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Efavirenz; Emtricitabine; Tenofovir: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Efavirenz; Lamivudine; Tenofovir Disoproxil Fumarate: (Moderate) Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Emtricitabine; Rilpivirine; Tenofovir alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Emtricitabine; Rilpivirine; Tenofovir disoproxil fumarate: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Emtricitabine; Tenofovir alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Emtricitabine; Tenofovir disoproxil fumarate: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Entecavir: Entecavir can affect kidney function and should be used cautiously with valacyclovir.

Fosphenytoin: Phenytoin and fosphenytoin are anti-seizure medications. The addition of valacyclovir to phenytoin may lead to a clinically significant decrease in phenytoin serum concentrations and loss of seizure control. Adjustments in phenytoin or fosphenytoin dosing should be considered if Valacyclovir is added or stopped when a patient is on either phenytoin and fosphenytoin.

Hyaluronidase, Recombinant; Immune Globulin: Immune Globulin (IG) products can damage the kidney. If they take any other drug that can affect the kidney, including valacyclovir, the dose of IG may need to be lowered and the infusion rate slowed.

Immune Globulin IV, IVIG, IGIV: Immune Globulin (IG) products can damage the kidney. If they take any other drug that can affect the kidney, including valacyclovir, the dose of IG may need to be lowered and the infusion rate slowed.

Lamivudine; Tenofovir Disoproxil Fumarate: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Measles Virus; Mumps Virus; Rubella Virus; Varicella Virus Vaccine, Live: (Major) If possible, discontinue valacyclovir at least 24 hours before administration of the varicella-zoster virus vaccine, live. Also, do not administer valacyclovir for at least 14 days after vaccination. The medication might have the unintended effect of diminishing the protective benefit of the vaccine.

Mycophenolate: (Moderate) Valacyclovir, when added to MMF, cyclosporine, and prednisolone caused a decrease in White Blood Cells, called neutropenia. When this combination must be used careful blood monitoring is recommended.

Phenytoin: Phenytoin is an anti-seizure medication. The addition of valacyclovir to phenytoin may lead to a clinically significant decrease in phenytoin levels and loss of seizure control. Adjustments in phenytoin dosing should be considered if valacyclovir therapy is added or discontinued.

Probenecid: Probenecid can reduce the kidney’s clearance of valacyclovir causing an increase in the blood level of valacyclovir. In the absence of a decrease in renal function, no dose adjustment is needed.

Talimogene Laherparepvec: “Consider the risks and benefits of treatment with talimogene laherparepvec before administering acyclovir or other antivirals to prevent or manage herpetic infection. Talimogene laherparepvec is a live, attenuated (lessened capacity to cause disease) herpes simplex virus that is sensitive to acyclovir; coadministration with antiviral agents may cause a decrease in efficacy.”

Telbivudine: Valacyclovir can affect kidney function. Since telbivudine is also cleared by the kidney, monitoring kidney function before and during telbivudine treatment is recommended.

Tenofovir Alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Tenofovir Alafenamide: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Tenofovir, PMPA: Tenofovir is primarily excreted via the kidneys, as is valacyclovir, so Tenofovir should not be used if a patient is on valacyclovir or has been on it recently.

Varicella-Zoster Virus Vaccine, Live: (Major) If possible, discontinue valacyclovir at least 24 hours before administration of the varicella-zoster virus vaccine, live. Also, do not administer valacyclovir for at least 14 days after vaccination. The medication might have the unintended effect of diminishing the protective benefit of the vaccine.


Sours: https://www.getroman.com/genital-herpes/valacyclovir-500mg/

Long does last how valacyclovir

Treating Shingles with Valtrex

Shingles is a disorder that can cause a lot of discomfort. Thankfully, there are some treatments that may be able to help.

Doctors, for example, may prescribe the medication valaciclovir (Valtrex) when you have shingles to help reduce the duration of your symptoms. Valtrex is an antiviral medication that can help stop the shingles virus from replicating.

The symptoms of shingles can last anywhere between . Valtrex doesn’t cure shingles, but it helps to keep the virus from multiplying. Here’s what you should know about how to reduce the duration of your symptoms last by taking Valtrex.

Maximizing the benefits of Valtrex for shingles

Shingles tend to follow a predictable pattern in terms of symptoms. The earlier you recognize the shingles by their pattern, the earlier you can seek treatment that may include Valtrex.

Most research regarding the effectiveness of Valtrex for shingles is when you start taking it within 72 hours after you first notice symptoms. Even if you don’t have immediately visible shingles lesions, your doctor can still perform testing to determine if you may have shingles.

If you wait too long, the virus have already replicated too much for the medication to be effective.

Side effects of Valtrex for shingles

The medication can cause some side effects. The most commonly known effects include:

  • dizziness
  • headache
  • nausea
  • stomach pain
  • vomiting

These side effects are usually mild. But there are some severe side effects that Valtrex can cause in some people. These include issues with kidney and nervous system function.

Severe side effects are more likely to occur in the elderly and those with pre-existing kidney disease. A doctor should discuss these and other possible side effects with you before prescribing Valtrex.

Takeaway

If you get shingles, starting Valtrex treatment as soon as possible may help to reduce the amount of days you have shingles symptoms. It could also help lessen shingles-related pain.

Talk to a doctor if you suspect you have shingles.

Sours: https://www.healthline.com/health/how-long-does-shingles-last-with-valtrex
Shingles: What You Should Know - Johns Hopkins Medicine

In this guide, we’ll look at some of the most common situations in which you’d use valacyclovir for treatment, as well as the approximate amount of time it should take for valacyclovir to offer relief.

>>MORE:How to get rid of a cold sore quickly.

Valacyclovir for First Herpes Outbreaks

For first-time herpes outbreaks, valacyclovir is most effective when it’s used within 48 hours of symptoms appearing.

The standard dosage of valacyclovir for first-time herpes outbreaks is 1,000 mg two times per day over a period of 10 days. Valacyclovir usually starts treating herpes symptoms as soon as it’s in your system, but can take several days to produce a noticeable improvement.

It can take up to 10 days (or, in some cases, even longer) for herpes blisters to heal even with valacyclovir treatment. This makes it important to start treatment as soon as you notice herpes symptoms.

In some cases, your doctor might prescribe valacyclovir for a longer period than 10 days or at a different dosage. In this case, follow your doctor’s instructions and make sure you complete the full course of the medication, even if the herpes blisters heal before the end of the period.

genital herpes treatment, 100% online

Some keep their breakouts at bay with a once daily pill. Connect with a healthcare provider and discover your treatment options.

Valacyclovir for Recurrent Herpes Outbreaks

Herpes can remain dormant in the body for weeks, months or years in between outbreaks. On average, people with HSV-1 experience about one outbreak per year, while people with HSV-2 will usually experience four to five outbreaks per year.

When these outbreaks occur, valacyclovir can provide fast and effective relief, helping to control herpes outbreak symptoms.

The typical valacyclovir dosage for recurrent herpes outbreaks is 500 mg two times per day over a period of three days. Like with first-time herpes outbreaks, valacyclovir is most effective when it’s taken as soon as you notice a herpes outbreak developing.

When taken as soon as you notice a herpes outbreak, valacyclovir can provide relief in as little as two to three days, minimizing symptoms and reducing the risk of you passing genital herpes to sexual partners.

>>MORE:HSV 1 vs. HSV 2 - What's the difference?

Valacyclovir for Shingles

Valacyclovir is usually prescribed for seven days for shingles, with a typical dosage of 1,000 mg three times per day.

Just like with HSV-1 and HSV-2, it’s important to start treatment as soon as you notice shingles symptoms. Most experts recommend starting valacyclovir within 72 hours of noticing symptoms for the best results.

Valacyclovir (Valtrex) for Cold Sores

For cold sores, valacyclovir is usually taken in two large doses of 2,000 mg, split 12 hours apart from each other. Like with other outbreaks of HSV, valacyclovir will speed up the speed at which cold sores heal, but it can still take seven to 10 days for them to fully disappear.

Worried About Herpes? Act Quickly for Faster Relief

From cold sores to genital herpes, acting quickly helps you treat and control a herpes outbreak in the shortest amount of time. For this reason, most doctors recommend using valacyclovir in the first 24-72 hours after noticing a cold sore or other herpes blister developing.

If you’ve noticed a cold sore or any of the other symptoms of a herpes outbreak, it’s best to talk to your doctor about treatment and relief options as soon as possible.

>>MORE:Is valacyclovir your best option? Read about others here.

Sours: https://www.forhims.com/blog/how-long-does-valacyclovir-valtrex-take-to-work

You will also like:

Valtrex side effects and interactions, and how to avoid them

If you’ve ever had shingles or cold sores, you know how uncomfortable these infections can be. Valtrex is an antiviral medication that can help relieve symptoms that come from viral infections like shingles or chickenpox. This article gives an overview of drug information including Valtrex side effects, warnings, and drug interactions that you should be aware of before taking the medication.

What is Valtrex?

Valtrex belongs to a group of medications called antivirals that work by slowing down the growth and spread of viruses like the herpes simplex, herpes zoster, and varicella-zoster viruses. Valtrex is the brand name for valacyclovir hydrochloride. The brand and generic versions of the medication are chemically the same, work the same way, and are equally effective at treating herpes virus infections.

Herpes virus infections include cold sores, genital herpes, shingles, and chickenpox. Valtrex can’t cure herpes infections, but it can treat symptoms like herpes sores and blisters. Valtrex is not an over-the-counter medication, so if you have a herpes infection, you’ll need a prescription.

It can take up to seven to 10 days for Valtrex to start working for some people, while others may feel relief from their symptoms after a day or two. The amount of time it takes your symptoms to go away will depend on your age, the severity of your symptoms, and your metabolism.

Valtrex for cold sores

Many people wonder whether Valtrex will stop cold sores from forming. Valtrex should be taken at the first signs of a cold sore (tingling, itching, burning) to prevent them from worsening and keep other cold sores from developing. However, it is not a cure for cold sores. It only treats them as a symptom of a viral infection.

Valtrex for genital herpes

Even if you’re taking Valtrex, it’s still possible to have an outbreak. If you’re taking Valtrex for recurrent genital herpes and have an outbreak, it’s important to avoid sexual contact with your partner to keep the virus from spreading to them. Even if you’re not experiencing an outbreak, using condoms is a good idea to prevent transmission. 

Also, if you’re wondering if your uninfected partner can take Valtrex to avoid becoming affected, the answer is no. Someone without herpes simplex virus shouldn’t take medication for something they don’t have. This could cause serious side effects or health problems. 

Common side effects of Valtrex

Taking Valtrex may cause side effects, such as:   

  • Headache 
  • Nausea
  • Stomach pain or abdominal pain 
  • Dizziness
  • Vomiting 
  • Weight gain
  • Irritability 
  • Tiredness
  • Trouble sleeping
  • Trouble concentrating
  • Loss of appetite
  • Skin rash
  • Bleeding gums
  • Sore throat 
  • Diarrhea  
  • Joint pain 

It’s unknown whether Valtrex causes other adverse effects like hair loss, weight gain, dry mouth, or any other symptoms not listed by the United States Food and Drug Administration (FDA). This is not a complete list of side effects. Other side effects may occur. Consult your healthcare provider if you have questions about side effects of Valtrex.

A frequently asked question about Valtrex is whether it will make you urinate more often. It won’t necessarily make you pee more, but you should drink plenty of water while taking Valtrex to help the kidneys process it as best they can. Therefore, this extra hydration can result in frequent urination.

Serious side effects of Valtrex

Although it’s rare, Valtrex can cause more serious side effects that may require medical attention, including:

  • Hallucinations
  • Aggressive behavior
  • Seizures
  • Confusion
  • Speech problems
  • Unusual bruising or bleeding
  • Depression
  • Low blood cell counts
  • Painful periods for women

If you’re taking Valtrex and have any of these symptoms, you should contact your doctor for medical advice as soon as possible. 

If you have any signs of an allergic reaction like difficulty breathing, hives, or swelling of the face, mouth, or throat, you should seek immediate emergency medical treatment.  

Other serious side effects that could potentially occur when taking Valtrex include: 

  • Inflammation of the liver
  • Renal toxicity
  • Kidney failure
  • A serious blood disorder called thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) 

Some patients are more susceptible to these serious side effects than others. Consult your healthcare provider to find out if you’re at risk.

These side effects are very rare. Antiviral medicines are effective at treating viral infections, but after long-term use, they can eventually weaken the immune system by affecting immune cells. This is typically only an issue for seniors and people with weakened immune systems. Even though it’s not typically taken for long periods of time, if your doctor does want you to take it long term, then that’s okay. Some studies have even shown that the long-term use of Valtrex is well-tolerated for healthy individuals.

If you start to have side effects from Valtrex and are thinking about stopping the medication, you should call your doctor before doing so. Abruptly stopping Valtrex can cause new side effects or worsen symptoms. If you stop Valtrex before you’re supposed to, your viral infection may get worse because the medication hasn’t had the opportunity to work properly. 

Valtrex warnings

Even though Valtrex is very effective at treating herpes virus infections, it shouldn’t be taken by everyone.

Underlying health conditions

You should talk with your doctor before taking Valtrex if you have any of the following medical conditions:

  • HIV: Having HIV suppresses the immune system and increases the probability of getting other medical conditions. People with HIV who take Valtrex significantly increase their risk of getting TTP/HUS, a serious blood disorder.   
  • Kidney or bone marrow transplants: If you’re taking Valtrex and are about to have a bone marrow or kidney transplant, you should talk with your doctor. Your risk of getting TTP/HUS will be significantly increased if you take Valtrex during your transplant process.
  • Kidney problems or kidney disease: People with kidney problems or kidney disease could experience a worsening of symptoms or kidney failure if they take Valtrex.

Because of its potential to negatively affect the kidneys, some people wonder if Valtrex is also hard on the liver, but studies have shown that it’s rarely associated with mild liver injury that resolves quickly.    

Age restrictions

If you are over the age of 65, it’s best to consult with your doctor before taking Valtrex. Elderly adults may have a higher risk of experiencing side effects and are more likely to have kidney problems because of it. This doesn’t mean that you can’t take Valtrex over the age of 65. Your doctor may simply recommend a lower dose.

Pregnancy and breastfeeding

Pregnant women should talk with a healthcare professional if they’re considering taking Valtrex to learn how it might affect their pregnancy. “Through laboratory testing, Valtrex had no effects on the fetus; nevertheless, Valtrex was not adequately tested with pregnant people,” says Vikram Tarugu, MD, a gastroenterologist and the CEO of Detox of South Florida. “The safety of Valtrex has not been proven in breastfeeding babies.” Women who are breastfeeding should consult their doctor about other approaches to feeding.  

Valtrex interactions

Taking Valtrex at the same time as certain other medications may cause additional side effects or complications. You should talk with your doctor before taking Valtrex if you’re on any of these medications:  

  • Foscarnet 
  • Acyclovir 
  • Famciclovir
  • Nephrotoxic agents 
  • Bacitracin 
  • Methotrexate 
  • Cancer medications
  • Arthritis medications 
  • Medications used to prevent organ transplant rejections 
  • Also, talk to your doctor if you’ve recently had a varicella virus vaccine (live) or zoster virus vaccine (live, Zostavax—not Shingrix)

Bring a complete list of all the prescription drugs and supplements you’re taking to your healthcare provider, so he or she can decide if Valtrex is right for you.     

There are currently no known interactions between Valtrex and grapefruit or grapefruit juice, which can sometimes interfere with how much of a drug stays in the body at one time. 

Alcohol, on the other hand, is best avoided while taking Valtrex. This is because when alcohol and Valtrex are combined, they can cause excessive drowsiness and dizziness.  

When it comes to caffeine and Tylenol, two of the things most likely to be consumed while on Valtrex, it’s okay to take them unless told otherwise by a medical professional.

How to avoid Valtrex side effects

1. Take the right dose at the right time of day

This is the best way to avoid Valtrex side effects. Here are the standard doses of Valtrex for adults and children:    

Valtrex dosages

Cold soresAdults2 g twice daily for one day taken 12 hours apart
Cold soresChildren (12 years and older)2 g twice daily for one day taken 12 hours apart
ShinglesAdults1 g three times daily for 7 days
ChickenpoxChildren with normal immune function (ages 2 years to <18 years)Dose is based on weight (20mg/kg) and given 3 times daily for 5 days. The total dose should not exceed 1 gram three times daily for 5 days.
Genital herpes (initial episode)Adults1 g twice daily for 10 days

These dosages are only general guidelines. If your doctor prescribes Valtrex differently, then you should follow their instructions. Valtrex is most effective when started as soon as symptoms begin, so see your doctor immediately if you have symptoms. It’s safe to take Valtrex every day as long as you’ve been instructed to do so.

If you miss a dose of Valtrex, you should take the next dose as soon as possible. Taking your missed dose as soon as you remember you’ve missed it will help keep your herpes infection from worsening. Taking two doses at one time can cause serious side effects, so if you’ve missed a dose, only take one dose when you remember. However, if it’s almost time for your next dose, skip the missed dose and resume your normal schedule. 

It’s also important to remember that Valtrex has an expiration date just like any other medication. Look for the expiration date on the prescription label to see how long your particular version of Valtrex is good for. Expired medications can be less effective and risky to take. Some medications are also sensitive to heat, so be sure to store Valtrex at room temperature.

2. Take Valtrex with a full glass of water.

This helps your kidneys process it more efficiently. Once it’s been taken, Valtrex starts working to treat symptoms right away. Even though it starts working right away, it may take several days for you to notice a difference in your symptoms.

3. Switch medications if necessary.

Acyclovir (brand name Zovirax) is another antiviral drug that can be used to treat herpes virus and varicella-zoster virus infections. Neither medication is better than the other, but if someone can’t tolerate Valtrex or has an underlying medical condition that prevents them from taking it, acyclovir is another good option.  You can compare the medications here.

Sours: https://www.singlecare.com/blog/valtrex-side-effects/


471 472 473 474 475