famciclovir at a glance
Medicine class
Oral antiviral; a prodrug of penciclovir
Usual uses
Shingles and genital herpes in adults
Food
Can be taken with or without food
Important check
Kidney impairment can substantially alter safe prescribing
What is famciclovir used for?
The selected product is licensed in adults for:
Shingles, including ophthalmic shingles, in people with a normal immune system
Shingles in immunocompromised adults
First and recurrent genital herpes episodes in immunocompetent adults
Recurrent genital herpes episodes in immunocompromised adults
Suppression of recurrent genital herpes in immunocompetent or immunocompromised adults
How does famciclovir work?
Famciclovir is rapidly converted to penciclovir. In herpesvirus-infected cells, penciclovir is activated and blocks viral DNA extension, limiting viral replication. It does not remove latent herpesvirus from the body.
famciclovir preparations and strengths
Tablet
Route: Oral
Strengths: 125 mg, 250 mg, 500 mg
How to take famciclovir
Take famciclovir exactly as prescribed and follow the supplied label.
It can be taken with or without food.
Do not share prescribed tablets with anyone else.
Do not drive or operate machinery if it causes dizziness, drowsiness or confusion.
famciclovir side effects
Common or expected effects
- Headache
- Feeling sick or vomiting
- Abdominal pain or diarrhoea
- Dizziness
- Rash or itching
- Abnormal liver blood tests
Get urgent medical advice
- Severe allergic reaction, including breathing difficulty or facial or throat swelling
- Severe blistering or peeling skin reactions
- Seizure
- Yellow skin or eyes
- Unexplained bruising, purple patches or bleeding
famciclovir in pregnancy
Experience with famciclovir during pregnancy is limited. The prescriber should review the potential benefits and risks and whether an antiviral with more pregnancy safety information is suitable.
famciclovir while breastfeeding
It is unknown whether famciclovir passes into human milk, and direct evidence is lacking. A prescriber or specialist should review whether it is necessary and discuss treatment and feeding options.
famciclovir interactions
Tell the prescriber or pharmacist about all medicines being taken. Particularly relevant examples include:
Probenecid
May reduce renal elimination of penciclovir and increase exposure. Adverse effects such as marked dizziness, drowsiness or confusion require attention.
Raloxifene
May inhibit conversion of famciclovir to active penciclovir, potentially reducing antiviral effectiveness.
Common questions about famciclovir
Answers are fully visible for fast scanning and source review.
What is famciclovir used for?
It is licensed in adults for shingles, including ophthalmic shingles, and for treating or suppressing genital herpes.
Is famciclovir an antibiotic?
No. It is an antiviral that acts against herpesviruses rather than bacteria.
Does famciclovir cure genital herpes?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.