Seizures in an Alzheimer's disease patient as a complication of colonoscopy premedication with meperidine.

We describe the first reported case of generalized tonic-clonic seizures induced by meperidine premedication for a colonoscopy procedure in a 63-year-old woman with Alzheimer's disease. The active metabolite of meperidine, normeperidine, is postulated to be the precipitating cause of the seizures, although a cholinesterase inhibitor and an N-methyl-D: -aspartate receptor antagonist, both routinely used for treatment of Alzheimer's disease, may have contributed by reducing the seizure threshold. The neuronal changes which occur in Alzheimer's disease can themselves also predispose to seizures.