A RANDOMIZED TRIAL OF ACYCLOVIR FOR 7 DAYS OR 21 DAYS WITH AND WITHOUT PREDNISOLONE FOR TREATMENT OF ACUTE HERPES-ZOSTER

Background. Acyclovir given for 7 to 10 days is of proved benefit in a cute herpes tester, but studies of its effectiveness in preventing pos therpetic neuralgia have had conflicting results. The role of corticos teroids in the treatment of herpes tester is also controversial. Metho ds. We conducted a double-blind, controlled trial in patients with acu te herpes tester to determine whether either 21 days of acyclovir ther apy or the addition of prednisolone offered any improvement over 7 day s of acyclovir therapy. Patients with a rash of less than 72 hours' du ration were assigned to receive acyclovir (800 mg orally, five times d aily) for 7 days with either prednisolone or placebo, or acyclovir for 21 days with either prednisolone or placebo. Prednisolone therapy was initiated at a dose of 40 mg per day and tapered over a three-week pe riod. Patients were assessed frequently through day 28 and then monthl y through month 6 to assess postherpetic neuralgia. Results. Of 400 pa tients recruited, 349 completed the study. No significant differences were detected between the four groups in the progression of the rash ( P>0.1). With steroid therapy, a significantly higher proportion of the rash area had healed on days 7 and 14 (P = 0.02). Pain reduction was greater during the acute phase of disease in patients treated with ste roids or 21 days of acyclovir(P<0.01 and P = 0.02, respectively, on da y 7; P<0.01 for steroid therapy on day 14). However, on follow-up ther e were no significant differences between any of the groups in the tim e to a first or a complete cessation of pain. The steroid recipients r eported more adverse events. Conclusions. In acute herpes tester, trea tment with acyclovir for 21 days or the addition of prednisolone to ac yclovir therapy confers only slight benefits over standard 7-day treat ment with acyclovir. Neither additional treatment reduces the frequenc y of postherpetic neuralgia.