Corneal Endothelial Dysfunction Associated With Amantadine Toxicity

Purpose: To describe bilateral corneal endothelial dysfunction in a patient with Parkinson disease who was treated with long-term amantadine. Methods: 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. Results: 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 <= 600/mm(2). Corneal edema recurred when the administration of amantadine was resumed. Therefore, amantadine was permanently discontinued and the cornea cleared again. Conclusions: Amantadine can cause reversible corneal edema but can irreversibly reduce the density of endothelial cells.