Is Your Herpes Medication Making You Sick?

by Charlotte Grayson, M.D. Health Professional

Herpes medications are generally safe, whether you are taking herpes antiviral medication to treat an outbreak or you're taking daily suppressive therapy.

But like all medications, the herpes antiviral DO have side effects. And you should know the difference between different herpes medicines so you can make the best decision for you and minimize any side effects.

Here's what you need to know:

The major drugs that doctors use to treat the herpes simplex virus (HSV) are antiviral agents called nucleosides and nucleotide analogues. They work by blocking reproduction of the herpes simplex virus. These drugs are acyclovir, valacyclovir, famciclovir. These drugs are oral medications. There are other antiviral similar to these drugs that are available in topical and intravenous formulations, but they are generally used to treat different viruses.

Acyclovir, Valacyclovir and famcyclovir can lessen the severity of a primary outbreak, reduce the time it takes genital herpes outbreaks to heal and can decrease the number of days of symptoms and days the virus is transmissible.

These antiviral medications are most effective when taken early in the course of an outbreak -- when you first feel the tingling and pain.

If you have a lot of outbreaks (more than 6 a year), studies show that taking antiviral medication daily to suppress the virus can reduce the frequency and duration of recurrent outbreaks.

The first pill for genital herpes was acyclovir. It is now generic, but its brand name was called Zovirax. It is approved to treatment of initial episodes and the management of recurrent episodes of genital herpes. It must be taken 3-5 times a day to be most effective. Because it is generic, it is the cheapest of the herpes medications.

Val acyclovir (Valtrex), is a prod rug of acyclovir. That means that the body converts it to acyclovir -- the active drug in the body. That helps more of the active drug get absorbed into the body. Thus, you need to take the drug less often than acyclovir. It is approved for treatment or suppression of genital herpes and for the suppression of recurrent genital herpes.

Famcyclovir (Famvir) is another prod rug -- but of the antiviral penciclovir. It is very similar to valacyclovir. Famcyclovir is approved for treatment or suppression of recurrent genital herpes.

So far, medical studies have not found any significant differences in effectiveness among the three medications. All are quite safe, very rarely producing any side effects at all.
All three of these oral antiviral drugs can be taken when a person has an outbreak or feels one coming on, or daily to help prevent the recurrence of outbreaks.

For the treatment of first genital herpes infections, acyclovir or valacyclovir is preferable to famciclovir. The efficacy of famciclovir for initial episode genital herpes infection has not been established.

For the treatment of recurrent infections, studies show that acyclovir, valacyclovir, and famciclovir have equal efficacy.

While most people tolerate the medication with no problems, a small percentage of people do experience side effects from daily antiviral therapy. These side effects are usually mild and include nausea, headache, nausea, stomach pain, cold, and sore throat.

Usually, these problems do not result in a person needing to stop the medication. To minimize side effects, try taking the medication with food. And be patient, most of the side effects are a nuisance, but do pass with each successive dose. However, if you find the side effects intolerable, talk to your doctor.

Rarely people can experience seizures and people with kidney disease should take the drugs at lower doses and with caution. Talk to your doctor if you are concerned about taking herpes medications. He or she can help guide you to the best treatment for you.

Charlotte Grayson, M.D.
Meet Our Writer
Charlotte Grayson, M.D.

Charlotte Grayson, M.D., is an internist in the Atlanta, Georgia, area. She is a 1995 graduate of Boston University School of Medicine. She completed her internal medicine residency in 1998 at the Medical University of South Carolina in Charleston. Previously, Dr. Grayson was Senior Medical Editor for a leading healthcare content company. She frequently speaks to the media about health, appearing on Fox News and CNN and contributing to TIME, Real Simple, Women’s Health, and WebMD magazines.