In a blind cross-over study, 12 patients with ventricular arrhythmias (VPC's; Lown Grades II-IVB) resistant to a daily dose of quinidine 1.2 g, disopyramide 0.8 g, N-propyl-ajmaline 0.1 g were randomly given, each dose for one week, placebo (PL), mexiletine (MEX; 400, 600, 800 mg daily) and
120 cases of class IC antiarrhythmic overdose, including propafenone, flecainide, ajmaline and prajmaline overdose, were evaluated with respect to clinical course, therapy and outcome. Whereas drug overdose in general has an overall mortality of less than 1%, intoxication with antiarrhythmic drugs