Flecainide, a class 1c antiarrhythmic, has a high mortality associated with significant overdose. We report the case of a 20-year-old female who took approximately 4 grams of flecainide and a small amount of paracetamol as an impulsive gesture. Circulatory failure unresponsive to pacing, inotropes and sodium bicarbonate was successfully treated with cardiopulmonary bypass (CPB). Resolution of her myocardial failure occurred over 24 hours and she was weaned from CPB 30 hours after its initiation. Coagulopathy and intravascular haemolysis were apparent during bypass and necessitated substantial use of blood products. Ischaemic renal dysfunction manifested early in her admission and required haemodiafiltration. Despite a prolonged period of unresponsiveness and pupillary dilatation during resuscitation and CPB she made a full recovery. We believe this is the first reported case of flecainide overdose, requiring extracorporeal circulatory support, not resulting in neurological deficit.