Myoclonus induced by metoclopramide therapy.

Metoclopramide hydrochloride is increasingly used as an antiemetic agent. Clinical and experimental studies have demonstrated dopamine antagonism, and extrapyramidal side effects have been reported in patients given the drug for gastrointestinal disorders. Multifocal myoclonic jerking developed in our patient after he received metoclopramide therapy for gastroparesis due to renal failure. He had had no previous neurologic symptoms, and no evidence of CNS abnormality was found; the myoclonic jerking subsided when metoclopramide therapy was discontinued. Multifocal myoclonus must be differentiated from seizure activity in patients with renal failure and other metabolic encephalopathies. Metoclopramide clearance is reduced in renal failure, and myoclonus or other neurologic complications may be precipitated in such patients by usual doses of this drug.