Corneal Endothelial Dysfunction Associated With Amantadine Toxicity

Abstract

To describe bilateral corneal endothelial dysfunction in a patient with Parkinson disease who was treated with long-term amantadine. We employed an A-B-A-B single-subject research design that included clinical history, clinical findings, photographic images, and specular microscopic findings of ocular changes. A 52-year-old woman with Parkinson disease who had taken amantadine for 6 years had bilateral corneal edema for 2 months at baseline. After cessation of amantadine, the edema resolved, and the endothelial cell densities were <or=600/mm. Corneal edema recurred when the administration of amantadine was resumed. Therefore, amantadine was permanently discontinued and the cornea cleared again. Amantadine can cause reversible corneal edema but can irreversibly reduce the density of endothelial cells.