We report a case of severe intoxication with extended-release verapamil. In addition to cardiovascular toxicities with hypotension, atrioventricular block and bradycardia, the patient suffered from grand-mal seizure and pulmonary edema 13 and 48 hours respectively, after ingestion of 4.8 g of extended-release verapamil. Adverse reactions after intoxications with extended-release tablets appear delayed with prolonged manifestation of symptoms. Early and repetitive administration of activated charcoal and antegrade whole bowel lavage are crucial, even in primary asymptomatic patients.