Fatal disopyramide intoxication from suicidal/accidental overdose

Disopyramide is an oral antiarrhythmic drug which reduces conduction velocity, prolongs duration of action potential and the effective refractory period, and exerts vagolytic properties. The drug is usually well absorbed orally. The principal use of the drug is to suppress ventricular extrasystoles with usual oral dosage of 100 to 200 mg every 6 h, until blood levels of 2 to 4 micrograms/mL are attained. The use of the drug for suicide is uncommon as it is a prescription drug. Two cases of fatal disopyramide intoxication seen at the Los Angeles County Medical Examiner's Office will be discussed followed by a review of the literature of fatal suicidal disopyramide overdose. Case 1 was a 31-year-old male pharmacist with known history of depression and no history of heart disease. His decomposed remains were found with a suicide note and with several disopyramide tablets. At autopsy the blood level for disopyramide was 146 micrograms/mL. Case 2 is a 40-year-old male with history of alcoholism and prior suicidal attempts who regularly took disopyramide to control ventricular arrhythmias. He apparently ingested 36 100-mg tablets of disopyramide before his final collapse. At autopsy his blood level of disopyramide was 63 micrograms/mL.