What is the dose of Famvir (famciclovir)?

From the Guidelines

Famvir (famciclovir) should be dosed at 250 mg orally three times a day for 7-10 days for the treatment of certain viral infections, as indicated by the most recent and relevant guidelines. When considering the treatment of viral infections, the dosage of Famvir is crucial for effective management.

• The standard treatment regimens for viral infections, such as herpes, include Famvir as an option, with specific dosing recommendations based on the type and severity of the infection.
• According to the guidelines from the Centers for Disease Control and Prevention, as outlined in the 1998 guidelines for treatment of sexually transmitted diseases 1, Famciclovir 250 mg orally three times a day for 7-10 days is a recommended regimen.
• It's essential to note that dosing may vary depending on the specific condition being treated, such as herpes zoster, genital herpes, or herpes labialis, and adjustments may be necessary for patients with kidney impairment.
• The mechanism of action of Famciclovir, which involves conversion to penciclovir and subsequent inhibition of viral DNA polymerase, supports its use in treating viral infections.
• Initiating treatment as soon as possible after symptom onset, ideally within a specific timeframe for certain conditions, is critical for maximizing effectiveness.
• Common side effects of Famciclovir, such as headache, nausea, and dizziness, are generally mild and transient, but should be monitored and managed accordingly.

From the FDA Drug Label

2.1 Dosing Recommendation in Immunocompetent Adult Patients Herpes labialis (cold sores):The recommended dosage of famciclovir tablets for the treatment of recurrent herpes labialis is 1500 mg as a single dose. Genital herpes: Recurrent episodes:The recommended dosage of famciclovir tablets for the treatment of recurrent episodes of genital herpes is 1000 mg twice daily for 1 day. Suppressive therapy:The recommended dosage of famciclovir tablets for chronic suppressive therapy of recurrent episodes of genital herpes is 250 mg twice daily. Herpes zoster (shingles):The recommended dosage of famciclovir tablets for the treatment of herpes zoster is 500 mg every 8 hours for 7 days.

The recommended dose of Famvir is as follows:

• Herpes labialis (cold sores): 1500 mg as a single dose
• Recurrent genital herpes: 1000 mg twice daily for 1 day
• Suppressive therapy for genital herpes: 250 mg twice daily
• Herpes zoster (shingles): 500 mg every 8 hours for 7 days 2 2

From the Research

Famvir Dose

• The dosage of Famvir for herpes zoster in immunocompetent individuals is 500 mg po tid for 7 days 3
• For recurrent genital herpes, a dosage of 125 mg po bid for 5 days is recommended 3
• Dosage adjustments are necessary in patients with renal dysfunction 3
• Famvir is also effective as therapy for recurrent episodes of genital herpes and may prove useful for chronic suppressive therapy 3
• Convenient patient-initiated single-day (for recurrent genital herpes) and single-dose (for orolabial herpes) dosage regimens may contribute to treatment compliance, patient acceptability and subsequent treatment outcomes 4

Administration and Efficacy

• Famciclovir has efficacy similar to that of aciclovir (in immunocompetent or immunocompromised patients) or valaciclovir (in immunocompetent patients) in the treatment of herpes zoster, and efficacy similar to aciclovir in the treatment of first or recurrent episodes of genital herpes (in immunocompetent or immunocompromised patients) 4
• Famciclovir also has efficacy in the suppression of recurrent episodes of genital herpes, and in the treatment of orolabial herpes, in immunocompetent patients 4
• Valaciclovir is more effective than acyclovir and equally effective as famciclovir at hastening the healing of zoster-associated pain and PHN 5

Comparison with Other Antiviral Agents

• Valaciclovir delivers therapeutic aciclovir concentrations when administered in a less frequent oral dosage regimen than is required for aciclovir 6
• Valaciclovir is an effective treatment for herpes zoster in immunocompetent adults, and is as effective as aciclovir in the treatment of genital herpes 6
• Famciclovir represents a viable alternative for treatment of herpes zoster and for episodic therapy of recurrent genital herpes in immunocompetent adults 3