Eyelash Hypertrichosis in a Patient Treated With Topical Latanoprost

We describe a female patient with a history of primary open-angle glaucoma who, following treatment with topical latanoprost, a synthetic prostaglandin F2α analog, developed hypertrichosis of the eyelashes. Hypertrichosis, a recently described side effect of latanoprost—together with iridal pigmentation—represents a potentially permanent cosmetic side effect associated with the use of this highly effective intraocular pressure–lowering agent. The molecular mechanism underlying latanoprost-induced hypertrichosis is unknown.