To treat a recurrent outbreak, the FDA recommends using 500 mg of Valacyclovir twice daily for 3 days starting at the first sign or symptom of lesions—preferably within 24 hours of onset. The CDC recommendation is identical but adds in the choice of using Valacyclovir 1 g (1000 mg) one time a day for 5 days. Valacyclovir 1 g taken every 12 hours for 5 to 14 days is recommended by the HIV guidelines. The Prescriber’s Digital Reference (PDR) also states, “There are no data supporting the effectiveness of beginning treatment more than 24 hours after the onset of symptoms.”
This information is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment, and should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your doctor.