Class Ic antiarrythmic overdose is associated with a relatively high mortality. We presenta case report regarding a suicidal intoxication of an 18-year old female with a medical history of Wolff-Parkinson-White syndrome. The preliminary examination highlighted a profound cardiovascular collapse. The electrocardiogram showed a PR interval extended to 360 ms. The QRS complexes were enlarged to 360 ms with a right bundle brunch block appearance associated with left posterior hemibloc. There were repolarization abnormalities such as elevation of the J-point, convex ST segment and biphasic T wave in the right precordial leads ("Brugada-Like ECG pattern"). Sodium bicarbonate was administered. A rapid decrease in the duration of the QRS complexes was noted as well as a slowing of the heart rate. The electrocardiogram aspect on the 4th day showed the reappearance of the ventricular pre-excitation. The severity and lethal potential of Flecainide poisoning are linked to the cardiotoxic effects of these molecules. The prognosis remains poor despite progress in intensive care procedures.