Active Ingredient

Famciclovir

Famciclovir is an antiviral medication commonly used to treat viral infections caused by herpes viruses. It helps manage conditions like shingles and genital herpes.

By reducing the activity of the virus, Famciclovir can help alleviate symptoms and speed up the healing process.

Written By Douglas C. Goldberg, MD

Reviewed By Philip Schein, MD

Last Updated 28 Nov 2025

Available Famciclovir Brands

Famvir

Strengths 250mg, 500 mg

Famciclovir Uses

Famciclovir is primarily used to treat infections caused by certain types of herpes viruses.

Treatment of shingles (herpes zoster)
Management of genital herpes outbreaks
Suppression of recurrent genital herpes
Treatment of cold sores (herpes labialis)
Management of herpes simplex infections in immunocompromised patients

How Famciclovir Works

Famciclovir works by inhibiting the replication of herpes viruses in the body. It targets the viral DNA polymerase enzyme, preventing the virus from multiplying.

This action helps to control the infection, reduce the severity of symptoms, and promote faster healing.

Common side effects of Famciclovir

Not everyone experiences side effects with Famciclovir, and many are mild and temporary. However, some common side effects may occur.

Headache
Nausea
Dizziness
Stomach upset
Fatigue
Diarrhea
Rash

If you experience severe or persistent symptoms, contact your healthcare provider.

Inform your doctor about any other medications you are taking to avoid potential interactions.
Avoid heavy alcohol consumption while using Famciclovir.
Do not use this medication if you have a known allergy to it or similar antiviral drugs.
Monitor your symptoms and report any unusual changes to your doctor.
Consult your doctor before using Famciclovir if you are pregnant or breastfeeding.

Always consult your healthcare provider for personalized medical advice.

Frequently Asked Questions

What is Famciclovir used for?

Famciclovir is used to treat infections caused by herpes viruses, such as shingles and genital herpes.

How quickly does Famciclovir work?

Famciclovir starts working soon after you begin taking it, but the time to see improvement can vary depending on the condition being treated.

Is Famciclovir safe for long-term use?

Famciclovir is generally safe for long-term use when prescribed by a doctor, especially for managing recurrent herpes infections.

Can I take Famciclovir with other medications?

It’s important to inform your doctor about all medications you are taking, as Famciclovir may interact with certain drugs.

Does Famciclovir cure herpes?

Famciclovir does not cure herpes but helps manage the symptoms and reduces the frequency of outbreaks.