Prophylactic oral acyclovir in recurrent genital herpes.

56 patients with frequently recurring genital herpes were treated in a randomised double-blind trial with either oral acyclovir 200 mg four times a day or placebo for 12 weeks. 29 patients received the drug and 27 the placebo. The mean recurrence rate per month of treatment was 1.4 in the placebo-treated patients and 0.05 in the acyclovir group. Median time to the first recurrence after the start of therapy was 14 days in the placebo group compared with 100 days in the acyclovir group. After the end of treatment the recurrence rate was similar in the two groups. Prophylactic oral acyclovir seems to be an effective treatment for patients with frequently recurring genital herpes.