Topical treatment of recurrent herpes simplex with cytosine arabinoside

A double-blind controlled clinical trial of the topical use of cytosine arabinoside in recurrent herpes simplex of the face and genital region showed no significant difference in the efficiency of a placebo as compared with cytosine arabinoside. The high rate of placebo response (70%) found in this trial makes the assessment of any drug treatment for herpes simplex particularly difficult.