Severe symptomatic atrioventricular block induced by pilocarpine eye drops

An 89-year-old man with chronic glaucoma received hourly pilocarpine eye drops for seven hours, when he developed third-degree atrioventricular block with a slow idioventricular escape rate. After discontinuing the pilocarpine, the atrioventricular block gradually disappeared. The site of pilocarpine-related block was most likely within the His-Purkinje system.