Effect of ketorolac on herpes simplex virus type one ocular infection in rabbits

Corticosteroids can exacerbate viral ocular infections. Ketorolac tromethamine is an effective nonsteroidal anti-inflammatory agent that may be a useful substitute for corticosteroids following ocular surgery. In this study, rabbits ocularly infected with herpes simplex virus type 1 (HSV-1) were treated topically four times daily with 0.5 percent ketorolac or 0.1 percent dexamethasone for 7 days after infection. Severity of the infection was determined by scoring corneal opacity and HSV-1 corneal ulcerations with the Draize scale as well as iritis and conjunctivitis. Ten days after treatment ended both the corneal opacity scores (1.5 out of 4) and HSV-1 corneal ulcerations (0.3 to 0.7 out of 4) were similar for ketorolac and the vehicle, indicating no exacerbation of the infection, whereas with dexamethasone these scores were increased (3.6/4 and 3.4/4, respectively). Furthermore, both iritis scores (0.5/2) and conjunctivitis scores (1.3 to 1.4/10) were also similar for ketorolac and the vehicle, while dexamethasone increased both iritis (1.8/2) and conjunctivitis (4.3/10) compared to vehicle. Thus, ketorolac appears to be an anti-inflammatory agent that does not worsen viral ocular infection.