Quinidine overdose. Neurological and cardiovascular toxicity in a normal person.

A case is described in which the ingestion of 4 g quinidine produced toxic effects involving mainly *the cardiovascular and central nervous systems identified by electrocardiographic conduction defects, hypotension, coma, and convulsions.Different modes of therapy are discussed as is the discrepancy between blood quinidine levels and the presence of symptoms.Since 1926 when Lewis and Drury investi- gated the pharmacological aspects of quini-,ine, there have been many reports on its toxic manifestations.Scientific investigation of toxicity has, of necessity, been carried out on animals.Luchi, Helwig, and Conn (I963) ,studied the toxic effects on the hearts of dogs.Cardiac toxicity in humans is usually reported as a clinical side effect during quinidine {therapy.We report a case of oral quinidine overdose as a suicide attempt in a patient with no previous history of cardiovascular or neuro- logical disease.Case report "The patient, a 57-year-old woman, ingested 20 200 mg quinidine tablets.When seen ij hours later at a Central Receiving Hospital, she was ataxic and lethargic.Vomiting was induced at that time, but no tablet residue was obtained.She was then transferred to the Los Angeles County-University of Southern California Medical Center.On arrival on the admitting ward, 3 'hours after ingestion of the tablets, she had a grand mal convulsion which recurred three times in the following 3 hours..4Physical examination Her skin was cold, moist, and cyanotic.The pulse was go a minute, poor volume and regular, blood pressure 50/20 jpmHg, respirations 24/minute, and temperature 370C.There was no jugular venous distension in the supine position.Praecordial examination revealed no heaves or thrills.The heart sounds were jistant with no murmur, rub, or gallop.