We report the case of a young anorexic woman who suffered a sudden loss of consciousness with convulsions, diagnosed as epilepsy associated with a migrational disorder, as documented at MRI. Standard 12-lead ECG showed a prolonged QT interval. Biochemical tests revealed a severe hypokalemia. Continuous 24-h ECG recording detected a ventricular tachycardia in torsades de pointes inducing a syncopal convulsive attack that seemed to be related to oral Cisapride assumption for dyspepsia. Discontinuation of cisapride and normalization of kalemia caused disappearance of both ECG abnormalities and loss of consciousness episodes. Syncope is a condition often misdiagnosed as epileptic seizures.