Long-term oral acyclovir treatment prevents recurrent genital herpes

Thirty-three patients with frequently recurring genital herpes completed a randomized double-blind, crossover trial with oral acyclovir 200 mg 4 times a day and placebo for periods of 12 weeks. Five patients (15%) had full recurrence during acyclovir treatment and 31 (94%) while receiving placebo. The median time to first recurrence was 20 days for placebo and more than 84 days for acyclovir. It was concluded that acyclovir was well tolerated and an effective treatment to suppress the disease in selected cases of severe and frequently recurring genital herpes. However, the relapses seem to occur with the same rate as before, when the suppressive acyclovir treatment is stopped.