Generic Name: Famciclovir

  • What is Famvir?

    Famvir is an antiviral medication used to stop/minimize the symptoms of recurrent genital herpes. It is also used to minimize the outbreaks of genital herpes, cold sores, and the rash and pain of shingles (herpes zoster).
  • What is the most important information I should know about Famvir?

    Famvir is not a cure for herpes. This drug may not stop the spread of herpes to others. If you are sexually active, you may still pass herpes to your partner while taking Famvir. Even if you are not currently having an outbreak, herpes may still be spread to your partner.
  • Who should not take Famvir?

    Do not use Famvir if you are allergic to any of its ingredients.
  • What should I tell my doctor before I take the first dose of Famvir?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Famvir. Also, talk to your doctor about your complete medical history, especially if you are over 65, have liver or kidney problems, or you are pregnant/planning to become pregnant or breastfeeding.
  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Adults: Recurrent Genital Herpes

    The usual dosage is two 500 milligram (mg) tablets as soon as you feel the beginning of an outbreak (within 6 hours), and two more tablets about 12 hours later.

    Suppression of Recurrent Genital Herpes

    The usual dosage is one 250 mg tablet in the morning and one at night. This treatment may continue for up to a year.

    Cold Sores

    The usual dosage is three 500 mg tablets taken all together at the first sign of an outbreak (within 1 hour).


    The usual dosage is 500 mg every 8 hours, for 7 days. Take the first tablet as soon as shingles in diagnosed (within 3 days of the first symptoms).

  • How should I take Famvir?

    Famvir can be taken with or without food.
  • What should I avoid while taking Famvir?

    Avoid engaging in unprotected sexual activity. Genital herpes may still be passed to your partner while you are on Famvir and/or you do not have visible sores.
  • What are possible food and drug interactions associated with Famvir?

    If Famvir is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Famvir with the following:


  • What are the possible side effects of Famvir?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: Diarrhea, fatigue, headache, nausea, stomach pain

  • Can I receive Famvir if I am pregnant or breastfeeding?

    The effects of Famvir during pregnancy and breastfeeding are unknown. Tell your doctor immediately if you are pregnant, plan to become pregnant, or are breastfeeding.
  • How should I store Famvir?

    Store at room temperature.