Famciclovir is an antiviral prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of two types of herpes simplex virus (HSV) infection in healthy adults: cold sores (also known as herpes labialis or orolabial herpes) and genital herpes. Famciclovir is also approved to treat shingles—a varicella zoster virus (VZV) infection—and to prevent the recurrence of genital herpes in healthy adults. In HIV-infected people, famciclovir is approved to treat herpes lesions in or around the mouth, genitals, and anal area.
VZV and HSV infections are opportunistic infections. An opportunistic infection is an infection that occurs more frequently or is more severe in people with weakened immune systems—such as those infected with HIV—than in people with healthy immune systems.
Famciclovir can also be used “off-label” to prevent and treat other opportunistic infections of HIV infection. “Off-label” use refers to use of an FDA-approved medicine in a manner different from that described on the medicine label. Good medical practice and the best interests of a patient sometimes require that a medicine be used “off-label.”
The Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents, prepared by the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), and the HIV Medicine Association of the Infectious Diseases Society of America (IDSA-HIVMA), includes recommendations on the HIV-related uses of famciclovir to:
Before taking famciclovir, tell your health care provider:
Ask your health care provider about possible side effects from famciclovir. Your health care provider will tell you what to do if you have side effects.
Take famciclovir according to your health care provider’s instructions. Your health care provider will tell you how much famciclovir to take and when to take it. Before you start famciclovir and each time you get a refill, read any printed information that comes with your medicine.
More information about famciclovir is available:
Last Reviewed: May 7, 2013
Last Updated: May 7, 2013