Description
Valacyclovir belongs to the class of medications known as antivirals. It is used to treat a viral infection affecting the skin known as shingles (herpes zoster). It is also used to treat cold sores, and to treat and prevent recurrences of genital herpes. It works by interfering with the way the virus reproduces. Valacyclovir works by stopping the virus from multiplying and spreading to nearby healthy cells.
It does not cure shingles, cold sores, or genital herpes, but it does help the sores to heal more quickly, and it relieves pain and discomfort. When used to prevent recurrences of herpes, it also reduces the risk of transmission (spreading) of the infection to others.
The recommended adult dose of valacyclovir to treat shingles is 1,000 mg 3 times daily for 7 days. The treatment should be started within 72 hours of the onset of the rash.
To treat the first episode of genital herpes, the dose of valacyclovir is 1,000 mg twice daily for 10 days. Treatment should be started within 72 hours of the onset of symptoms, and ideally within 48 hours for best effectiveness.
To treat recurrent genital herpes, the dose of valacyclovir is 500 mg twice daily for 3 days. The treatment should be started at the first sign or symptom of recurrence.
To prevent recurrences of genital herpes, the recommended dose is 1,000 mg once daily. For people with a history of 9 or fewer recurrences per year, the recommended dosage of valacyclovir is 500 mg orally once daily. This dose helps to reduce the risk of transmitting genital herpes to others.
To treat cold sores, the usual dose of valacyclovir is 2,000 mg at the first sign of symptoms, followed by another 2,000 mg 12 hours later. The treatment should be started at the first sign of a cold sore (tingling, itching, or burning sensations) for best effectiveness.
People with poor kidney function may need lower doses.
