Latanoprost and herpes simplex keratitis.

PURPOSE: To report three cases in which herpes simplex keratitis developed after initiation of latanoprost therapy.
METHODS: Case report.
RESULTS: One patient with a history of herpes simplex keratitis had recurrence of herpes simplex keratitis with latanoprost treatment, resolution when latanoprost was stopped, and another recurrence when rechallenged with latanoprost. A second patient with a history of herpes simplex keratitis had bilateral recurrence with initiation of latanoprost; antiviral therapy could not eradicate herpes simplex keratitis until the latanoprost was discontinued. The third patient with latanoprost-associated herpes simplex keratitis cleared with the discontinuation of latanoprost and start of antiviral therapy; reinstitution of latanoprost with prophylactic antiviral medication kept the cornea clear, but as soon as the antiviral suppression was discontinued, herpes simplex keratitis reappeared.
CONCLUSION: Latanoprost, among its diverse pharmacologic effects, may mediate inflammation in the eye. Prostaglandins may be a final common pathway for stimulating recurrence of herpes simplex keratitis. Clinicians should be aware of this possible association.