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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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


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.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


A synthetic nucleoside analog, C14H19N5O4, used to treat herpes simplex and herpes zoster infections.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


An antiviral drug used to treat SHINGLES and genital HERPES. A brand name is Famvir.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


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
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Previous data showed that, when taken within 6 hours of symptom onset, single-day famciclovir (Famvir, 1,000mg b.i.d.) increased the proportion of patients with aborted episodes from 13% to 23%, and reduced healing time and duration of symptoms by 2 days, vs.
Treatment with topical trifluridine in OD and systemic famciclovir was started.
Previous data showed that, when taken within 6 hours of symptom onset, single-day famciclovir (Famvir, 1,000 mg b.i.d.) increased the proportion of patients with aborted episodes from 13% to 23%, reduced healing time by 2 days, and reduced duration of symptoms by 2 days, compared with placebo (Clin.
But high doses of antiviral drugs--Zovirax (acyclovir), Valtrex (valacyclovir), or Famvir (famciclovir)--can control reproduction of the varicella zoster virus in the nerve cells, significantly reducing the pain and duration of a shingles attack.
A partial list of these medications includes ciprofloxacin, erythropoietin, lamivudine (for the treatment of hepatitis B), fluconazole, ketoconazole, itraconazole, ganciclovir (to treat CMV), ribavirin and interferon (to treat hepatitis C), rifabutin (to treat MAI), and famciclovir (to treat Herpes Simplex).
Antiviral drugs such as famciclovir (Famvir) are used with mixed results.
Prescription antiviral medicines--including Zovirax (acyclovir), Famvir (famciclovir), and Valtrex (valacyclovir)--may help speed healing and reduce shingles pain if taken within the first 72 hours of symptoms.
The patient was treated with famciclovir (500 mg three times a day for 7 days).
When she writes a prescription for one of the newer antiviral therapies such as famciclovir or valacyclovir, she also give the parent a back-up prescription for acydovir, just in case the insurance company won't cover the drug of first choice.
Identifying the infection early, in part by the purple tongue, allowed zookeepers in Missouri to save one young elephant with massive doses of the human herpes drug famciclovir.
Other agents, ganciclovir and famciclovir, have shown antiviral activity against HCV [54].
Famciclovir, the prodrug of penciclovir, is more effective than valacyclovir at resolving acute herpes zoster rash and shortening the duration of PHN.