What is famciclovir?
Famciclovir is an antiviral drug. It slows the growth and spread of the herpes virus so that the
body can fight off the infection. Famciclovir will not cure herpes, but it can lessen the symptoms of the
infections.
Famciclovir is used to treat infections caused by herpes viruses, including genital herpes, cold
sores, shingles, and chicken pox.
There is no cure for herpes and famciclovir will not prevent you from developing symptoms in
the future.
Famciclovir may also be used for other purposes not listed in this medication guide.
What should I discuss with my healthcare provider before taking famciclovir?
Do not take famciclovir if you are allergic to penciclovir cream (Denavir).
If you have any of these other conditions, you may need a dose adjustment or special tests to
safely use this medication:
FDA pregnancy category B. This medication is not expected to be
harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during
treatment.
Your name may need to be listed on a pregnancy registry if you become pregnant while using
this medication. The purpose of this registry is to track the outcome of the pregnancy and delivery to
evaluate whether famciclovir had any effect on the baby.
It is not known whether famciclovir passes into breast milk, or if it could harm a nursing
baby. Do not take famciclovir without telling your doctor if you are breast-feeding a baby.
Do not give this medication to a child younger than 18 years old.
How should I take famciclovir?
Take this medication exactly as it was prescribed for you. Do not take the medication in larger
amounts, or take it for longer than recommended by your doctor. Follow the directions on your
prescription label.
Treatment with famciclovir should be started as soon as possible after the first appearance of
symptoms (such as tingling, burning, blisters).
Take each dose with a full glass of water. Drink plenty of water while you are taking
famciclovir to keep your kidneys working properly.
Famciclovir can be taken with or without food. Taking famciclovir with food may decrease
stomach upset.
Take this medication for the entire length of time prescribed by your doctor. Your
symptoms may get better before the infection is completely treated. To prevent recurrent genital
herpes, you may need to take famciclovir twice daily for up to 1 year. Follow your doctor's
instructions.
Lesions caused by herpes viruses should be kept as clean and dry as possible. Wearing loose
clothing may help to prevent irritation of the lesions.
Store famciclovir at room temperature away from moisture and heat.
What happens if I miss a dose of famciclovir?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the
missed dose and take the medicine at the next regularly scheduled time.
Do not
take
extra medicine to make up the missed dose.
Where can I get more information about famciclovir?
Your pharmacist has information about famciclovir written for health professionals that you may read.
What are the possible side effects of famciclovir?
Get emergency medical help if you have any of these
signs of an allergic
reaction:
hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Less serious side effects may include:
-
nausea, vomiting, stomach pain;
-
diarrhea,
-
headache, tired feeling;
-
dizziness, sleepiness;
-
mild itching or skin rash;
-
numbness or tingly feeling; or
-
confusion.
This is not a complete list of side effects and others may occur. Call your
doctor for medical advice about side effects. You may report side effects to FDA at
1-800-FDA-1088.
What is the most important information I should know about famciclovir?
Take this medication for the entire length of time prescribed by your doctor. Your
symptoms may get better before the infection is completely treated.
Treatment with famciclovir should be started as soon as possible after the first appearance of
symptoms (such as tingling, burning, blisters).
Herpes infections are contagious and you can infect other people, even while you are being
treated with famciclovir. Avoid letting infected areas come into contact with other people. Avoid
touching an infected area and then touching your eyes. Wash your hands frequently to prevent passing
the infection to others.
What should I avoid while taking famciclovir?
Herpes infections are contagious and you can infect other people, even while you are being
treated with famciclovir. Avoid letting infected areas come into contact with other people. Avoid
touching an infected area and then touching your eyes. Wash your hands frequently to prevent passing
the infection to others.
Famciclovir will not prevent the spread of genital herpes. Avoid sexual intercourse or use a latex
condom to prevent spreading the virus to others.
Famciclovir can cause side effects that may impair your thinking or reactions. Be careful if
you drive or do anything that requires you to be awake and alert.
What other drugs will affect famciclovir?
Before taking famciclovir, tell your doctor if you are also taking probenecid (Benemid). If you
are using probenecid, you may not be able to use famciclovir, or you may need dosage adjustments or
special tests during treatment.
This list is not complete and there may be other drugs that can interact with famciclovir. Tell
your doctor about all the prescription and over-the-counter medications you use. This includes
vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new
medication without telling your doctor.
What happens if I have an overdose of famciclovir?