Adenine arabinoside possessed all of the desirable characteristics for an antiviral agent: (1) not incorporated into host DNA; (2) broad spectrum activity against the DNA family of viruses; (3) lack of resistance in vitro; (4) rapid excretion; (5) did not cause immunosuppression; (6) low toxicity in significantly effective doses; and (m7) relatively inexpensive. Adenine arabinoside employed in 20 mg/kg1day intravenous infusions for seven days in a controlled series of patients was clearly effective in treating herpetic keratouveitis with only minimal adverse reactions. For the first time there may be an effective specific treatment for herpetic stromal disease and iritis. Further controlled studies comparing the effectiveness of adenine arabinoside with and without concommitant topical corticosteroid therapy are necessary.