Massive diltiazem overdose.

A 74-year-old man presented with bradycardia, diaphoresis, mental confusion, and slurred speech. He developed asystole and was managed successfully with temporary emergency transvenous pacing and support of ventilation and blood pressure. He later was found to have ingested approximately 1,500 mg diltiazem, apparently as the result of an error created by his blindness and chronic confusion.