 - Known prolongation of the QT interval or concomitant use of drugs reported to increase the QT interval e.g. Class IA or Class III antiarrhythmics eg., quinidine, procainamide, amiodarone, sotalol, neuroleptics e.g. haloperidol, tricyclic antidepressive agents, certain antimicrobials e.g. pentamidine, halofantrine, certain antihistaminics e.g. terfenadine, and other cisapride, vincamine IV, depridil, diphemanil 