Propafenone is a class Ic antiarrhythmic agent which also exhibits beta-adrenergic and fast sodium channel blockade. We report a case of severe poisoning in a 24-y-old woman who suffered a seizure 1 h after the intentional ingestion of 2.7 g propafenone, and had a recurrence of convulsion on arrival at the hospital. She also developed severe arrhythmia during her hospital course. She recovered uneventfully with supportive treatment.