Possible retinotoxic effect of carbamazepine

Two cases of retinopathy possibly caused by the antiepileptic drug, carbamazepine (Tegretol) are presented. Two female patients in middle age with epilepsy had been treated with carbamazepine for more than 7 years when they experienced sudden visual disturbances and reduction of visual acuity without known concomitant systemic toxic effects. Ophthalmoscopy, fundus colour photography and fundus fluorescein angiography disclosed in one patient discrete, and in the other patient extensive lesions of the retinal pigment epithelium in the posterior poles of the eyes including the macular regions. Discontinuation of carbamazepine led to improvement of visual function and of the morphological changes in the fundi of the patient with the most pronounced lesions. It is suggested that carbamazepine, a drug nearly chemically identical with the tricyclic psychotropic agents, might cause damage of the retinal pigment epithelium in long-term treatment. Further clinical controlled studies of the possible retinotoxic effect of this agent are, however, required.