[Case in which magnesium sulfate effectively treated ventricular tachycardia due to overdose of pilsicainide hydrochloride].

A 34-year-old man ingested an excessive amount of pilsicainide hydrochloride (Sunrythm, total dose, 2,500 mg) with suicide attempt. On admission, consciousness was impaired and circulatory failure was evident. Systolic blood pressure was 74 mmHg. As electrocardiography (ECG) revealed ventricular tachycardia (VT), cardioversion was administered but was unsuccessful. We therefore administered magnesium sulfate. This resulted in immediate reversion to normal rhythm; however, PQ and QRS intervals remained prolonged, consistent with the effects of a Vaughan Williams class I c Na-channel blocker. Blood pressure rose to over 100 mmHg, and circulatory and respiratory function improved immediately. Plasma concentration of pilsicainide hydrochloride was markedly increased to 7.22 microg/mL (therapeutic range: 0.2 approximately 1.0 microg/ mL) on admission. We performed direct hemoperfusion (DHP) to reduce pilsicainide concentration. DHP was performed twice, and drug concentration was measured each time. DHP was insufficiently effective for reducing plasma pilsicainide concentration. In conclusion, administration of magnesium sulfate is an effective therapy for Pilsicainide-induced ventricular tachycardia.