Valacyclovir

Valacyclovir is an antiviral drug used to treat oral herpes (also known as cold sores) and genital herpes caused by herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2). It is also used to treat varicella zoster virus (VZV), the virus that causes chickenpox and shingles. It is also sometimes used for cytomegalovirus (CMV) and Bell’s Palsy, but these uses are not FDA-approved and are considered “off-label”. Physicians on the Roman platform prescribe valacyclovir for the treatment of genital herpes and oral herpes only. If you feel that you need valacyclovir for any other condition, please seek in-person care. Note that valacyclovir is not an antibiotic. Antibiotics fight bacteria whereas antivirals are active against viruses, which are technically not even alive.

Valacyclovir can be used to treat genital herpes and oral herpes in several ways, depending on the goal. It can be used to:

• Treat initial and recurrent outbreaks of genital herpes

• Treat initial and recurrent outbreaks of oral herpes

• Prevent outbreaks of genital herpes

• Prevent outbreaks of oral herpes (an “off-label” use)

• Decrease the risk of transmitting herpes to a partner by decreasing viral shedding (viral shedding is when the virus is found on the skin or mucous membranes. This can occur without symptoms and is called asymptomatic shedding)

Valacyclovir was initially FDA-approved to treat herpes simplex infections in 1995 as the brand name drug Valtrex®, and has been used since then with a safety profile that is similar to placebo even when used for long periods. It is effective at shortening the duration of symptoms when used for treating initial and recurrent outbreaks of genital herpes and oral herpes and at decreasing the number of outbreaks when used daily to prevent outbreaks. Daily use is also effective for decreasing the risk of spreading genital herpes to an uninfected partner. If you suffer from recurrent outbreaks of oral or genital herpes, your doctor may prescribe valacyclovir to treat or suppress outbreaks.

Herpes viruses are basically just DNA wrapped in a protein coating. In order for the virus to be able to multiply, it needs to first replicate its DNA. Valacyclovir acts through multiple mechanisms to prevent the replication of herpes DNA. It is active against HSV-1, HSV-2, VZV, and to a lesser extent other herpes viruses, like CMV. When viral DNA is prevented from replicating, the virus cannot multiply and infect uninfected cells. This is how valacyclovir works:

• Aborts (stops) or shortens outbreaks of genital herpes, oral herpes, and shingles

• Prevents outbreaks of genital and oral herpes

• Decreases the risk of viral transmission to the uninfected partner

Once in the blood, valacyclovir starts to work almost immediately. Since it specifically attacks the DNA replication process, it will only attack herpes viruses that are reproducing; so while it starts to work on an active infection very quickly, it will not fight the virus that is inactive and hiding in the nervous system.

Nevertheless, if taken on a daily basis it may reduce the number of outbreaks a person might experience by 70%–80% and reduce the risk of transmitting herpes to a partner by about 50%. Taken at the earliest feelings that an outbreak is on the verge of occurring, valacyclovir may either abort the attack or shorten how long it will last. Remember, with valacyclovir treatment for herpes, the earlier you take it after the symptoms appear, the better.

While it goes to work within hours of taking the medication, the symptoms and sores of an actual outbreak may take days to begin to heal and the virus can stay active throughout the healing process.

Valacyclovir is an antiviral medication that is used to treat oral herpes and genital herpes, which are caused by herpes simplex viruses 1 and 2 (HSV-1 and HSV-2). It is also FDA-approved for the suppression and reduction of transmission of genital herpes.

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

It’s important to take the medicine at the first sign or symptom because there is no evidence that the medication works once lesions are visible. Most people will be able to tell when an outbreak is coming on. They may experience burning, itching, tingling, or other sensations that alert them to an imminent outbreak.

Take two tablets of valacyclovir 1,000 mg (2,000 mg total) followed by another two 1,000 mg tablets 12 hours later. Make sure to stay hydrated by drinking fluids throughout the day. For those who are HIV-infected, the recommended dose is 1 gram (1000 mg) every 12 hours for 5 to 10 days.

Treatment with suppressive therapy

Valacyclovir is not approved for suppressive therapy of oral herpes, but doctors have the discretion to prescribe it for this use if they believe that it is an appropriate course of treatment for a particular patient. This is considered off-label treatment. It is up to the medical judgment of the doctor to decide if off-label treatment is appropriate for a patient based on the patient’s unique medical history, symptoms, and preferences. Physicians who choose to prescribe valacyclovir off-label for the suppression of oral herpes may recommend 500 mg or 1,000 mg once daily.

Treatment of initial genital outbreak

To treat an initial episode of genital herpes, 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 recurrent genital herpes, including HIV-infected patients

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 also recommends valacyclovir 500 mg twice daily for 3 days, but adds an alternative regimen of 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.

Treatment with suppressive therapy

People with less than 10 outbreaks per year should take valacyclovir 500 mg once daily. Valacyclovir 1,000 mg once daily is recommended for people with 10 or more outbreaks per year.

To prevent transmission to a partner

The infected partner should take valacyclovir 500 mg once a day to decrease the risk of transmission to the uninfected partner. The data are strong but refer to patients with 9 or fewer outbreaks each year.

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

Valacyclovir comes in two doses, 500 mg and 1,000 mg tablets. Although there are only two doses, there are several different ways to use the medicine for different indications. Below is a summary of how to use valacyclovir. Keep in mind that these doses may need to be changed for people with specific conditions, such as kidney problems. If you’re prescribed valacyclovir, take it according to your prescriber’s instructions.

For genital herpes:

To Treat Or Abort An Outbreak When There Are Early Symptoms (Prodrome)

Some patients 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 and make an outbreak milder than it might have been 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. They know when they are more likely to have an outbreak due to their circumstances. They can avoid their triggers but they also might want to take medication preventatively knowing when they are more vulnerable. Essentially they might take the medication for a week or two until the circumstance that is making them more susceptible to an outbreak has resolved.

To Suppress Outbreaks For An Extended Period

Patients can take medication when they would like to do all they can to reduce their chance of having an outbreak. The classic example would be during a honeymoon, going on vacation, starting a new job, in a new relationship, or at any time a patient feels it is how they want to keep the chance of having an attack as low as possible.

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. Valacyclovir not only reduces the number of outbreaks a person experiences but it reduces asymptomatic shedding. 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.

For oral herpes:

To 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 for the use of medication once lesions have appeared.

Acyclovir was the first antiviral drug for the treatment of herpes infections. Acyclovir was initially FDA-approved to treat herpes simplex infections in 1985 as the brand name drug Zovirax® and was found to be very effective for treating herpes infections. The main problem with acyclovir is that only 10%–20% of it is absorbed from the digestive tract. To make matters worse, higher doses have worse absorption than lower doses. This made it very difficult to maintain a high enough level of the drug in the blood to be effective, requiring patients to take up to five doses per day.

Valacyclovir is considered a prodrug of acyclovir, which means that it is converted into acyclovir in the body. Since valacyclovir is absorbed much better than acyclovir (54% for valacyclovir vs 10%–20% for acyclovir), it can be dosed less frequently and get equal or better results compared to acyclovir. Valacyclovir is dosed from 1 to 3 times daily, depending on what it’s being used for, whereas acyclovir is used 2 to 5 times daily depending on the indication. Valacyclovir is generally preferred by doctors and patients because it is easier to dose and may be more effective.

Cold sores are caused by a herpes virus that may be spread by kissing or other physical contact with the infected area of the skin. They are small, painful ulcers that you get in or around your mouth. It is not known if valacyclovir tablets can stop the spread of cold sores to others.

Chickenpox is caused by a herpes virus called Varicella Zoster Virus (VZV). It causes an itchy rash of multiple small, red bumps that look like pimples or insect bites usually appearing first on the abdomen or back and face. It can spread to almost everywhere else on the body and may be accompanied by flu-like symptoms.

Shingles is caused by the same herpes virus that causes chickenpox. It causes small, painful blisters to appear on your skin. Shingles occurs in people who have already had chickenpox. Shingles can be spread to people who have not had chickenpox or the chickenpox vaccine by contact with the infected areas of the skin. It is not known if valacyclovir tablets can stop the spread of shingles to others.

Genital herpes is a sexually transmitted disease. It causes small, painful blisters on your genital area. You can spread genital herpes to others, even when you have no symptoms. If you are sexually active, you can still pass herpes to your partner, even if you are taking valacyclovir tablets. Valacyclovir tablets, taken every day as prescribed and used with the following safer sex practices, can lower the chances of passing genital herpes to your partner.

Do not have sexual contact with your partner when you have any symptom or outbreak of genital herpes. Use a condom made of latex or polyurethane whenever you have sexual contact. Ask your healthcare provider for more information about safer sex practices.

Valacyclovir is available as a pill. The pills can be blue or white in appearance, depending on the manufacturer. What’s important is that regardless of what the color of the pill is, the active ingredient is valacyclovir. The color of the pill will not affect how effective your medication is.

Valacyclovir is not an antibiotic. Valacyclovir is an antiviral drug with activity against the herpes simplex viruses 1 and 2 (HSV-1 and HSV-2). Valacyclovir attacks the DNA replication process of the virus, so it only attacks herpes viruses that are attempting to actively reproduce. While valacyclovir is an antiviral drug that works on active infections, it will not fight the virus that is inactive and hiding in the nervous system.