Also found in: Dictionary, Wikipedia.
Related to famciclovir: shingles


a prodrug of penciclovir that is converted to the active drug following administration, used in the treatment of herpes zoster, of genital herpes, and of mucocutaneous herpes simplex in immunocompromised patients; administered orally.


Apo-Famciclovir (CA), Famvir, PMS-Famciclovir (CA), Sandoz Famciclovir (CA)

Pharmacologic class: Synthetic nucleoside

Therapeutic class: Antiviral

Pregnancy risk category B


Converts to penciclovir and selectively inhibits DNA polymerase and viral DNA synthesis


Tablets: 125 mg, 250 mg, 500 mg

Indications and dosages

Acute herpes zoster infection (shingles)

Adults: 500 mg P.O. q 8 hours for 7 days

Recurrent genital herpes in immunocompetent patients

Adults: 1,000 mg P.O. b.i.d. for 1 day, starting as soon as symptoms appear

Suppression of recurrent genital herpes

Adults: 250 mg P.O. b.i.d. for up to 1 year

Recurrent herpes simplex infection in patients with human immunodeficiency virus

Adults: 500 mg P.O. b.i.d. for 7 days

Herpes labialis (oral herpes simplex) in immunocompetent patients

Adults: 1,500 mg P.O. as a one-time dose given as soon as symptoms appear

Dosage adjustment

• Renal impairment


• Hypersensitivity to drug or its components


Use cautiously in:
• renal or hepatic impairment
• elderly patients
• pregnant or breastfeeding patients
• children younger than age 18.


• Know that for best response, therapy should begin within 6 hours of onset of genital herpes symptoms or lesions.
• Give with or without food.

Adverse reactions

CNS: headache, fatigue, dizziness, drowsiness, paresthesia, insomnia

EENT: pharyngitis, sinusitis

GI: nausea, vomiting, diarrhea, constipation, abdominal pain, anorexia

Musculoskeletal: back pain, joint pain

Skin: pruritus, rash

Other: fever


Drug-drug.Digoxin: increased digoxin blood level, increased risk of toxicity

Probenecid: increased blood level of penciclovir (active antiviral compound of famciclovir)

Patient monitoring

• When giving concurrently with digoxin, monitor digoxin blood level and evaluate for digoxin toxicity.
• Monitor CBC, blood urea nitrogen, creatinine, and electrolyte levels.
• Be aware that drug may take several weeks to reach therapeutic level.
• Know that renal failure may raise blood drug level, increasing the risk of adverse reactions.
• Avoid direct contact with infected areas. Wash hands frequently and wear gloves during patient contact.

Patient teaching

• Instruct patient to take with food or milk to avoid upset stomach.
• Inform patient that drug doesn't cure herpes but only decreases pain and itching by allowing sores to heal and preventing new ones from forming.
• Advise patient to wear loose-fitting clothing to avoid irritating lesions.
• Tell patient to report rash or itching.
• Instruct female patient to tell prescriber if she is pregnant or breastfeeding.
• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs mentioned above.


/fam·ci·clo·vir/ (fam-si´klo-vir) a prodrug of penciclovir used in the treatment of herpes zoster, of herpes genitalis, and of mucocutaneous herpes simplex in immunocompromised patients.


A synthetic nucleoside analog, C14H19N5O4, used to treat herpes simplex and herpes zoster infections.


an antiviral drug.
indications It is prescribed in the treatment of acute herpes zoster and recurrent genital herpes.
contraindications It should not be given to patients with kidney disease or an allergy to famciclovir. The safety of the drug in children or in women who are pregnant or breastfeeding has not been established.
adverse effects The side effects most often reported include fatigue, fever, pain, chills, headache, dizziness, nausea, diarrhea, vomiting, and constipation.


An antiviral drug used to treat SHINGLES and genital HERPES. A brand name is Famvir.


An oral antiviral drug that is available under the trade name Famvir. The drug blocks the replication of the varicella zoster virus.
Mentioned in: Shingles


n brand name: Famvir;
drug class: antiviral;
action: converted to active metabolite, peniciclovir triphosphate, which inhibits viral DNA synthesis and replication;
uses: acute herpes zoster (shingles) infection.
References in periodicals archive ?
Though acyclovir is significantly less expensive, famciclovir and valacyclovir are preferred due to more convenient dosing regimens (5 times daily versus 3 times daily, respectively).
There is far less pregnancy data for valacyclovir and famciclovir, raising questions about the risk of these antivirals.
Previous data showed that, when taken within 6 hours of symptom onset, single-day famciclovir (Famvir, 1,000mg b.
In people who have had at least one outbreak of blistering from genital herpes, the drug famciclovir sharply reduces virus shedding from the external portions of the genitalia, a new study finds.
Famciclovir the treatment of acute herpes zoster: effects on acute disease and postherpetic neuralgia: a randomized, double-blind, placebo-controlled trial.
lamivudine, lobucavir, famciclovir, adefovir) to inhibit polymerase activity.
Gilbert et al (29) described a 34-year-old male with HIV and a 5-month history of HSV-2 infection refractory to acyclovir, valacyclovir, or famciclovir that was eradicated with a 1-week course of topical imiquimod.
Antiviral drugs such as famciclovir (Famvir) are used with mixed results.
acyclovir, famciclovir, and valacyclovir) have exhibited no teratogenic effects in animal or human pregnancies, and they are listed in category B.
Both of these are secondary mutations and have previously been described as associated with famciclovir treatment (4, 8).
The list includes VIDEX EC, alendronate, valacyclovir, famciclovir, kineret and pegetron.
16) * Herpes Simplex Virus Antiviral medications such (viral) as acyclovir, famciclovir, - 45 million people valacyclovir, can treat and currently infected prevent outbreaks, but - 1 million new cases herpes cannot be cured.