- Treatment with any medication that causes QT prolongation or Torsades de Pointes within 7 days prior to initiation of study drug, including but not limited to: Cisapride, pimozide, astemizole, terfenadine, ergotamine, dihydroergotamine, quinidine, procainamide, disopyramide, sotalol, ibutilde, dofetilide, dronedarone, ondansetron or other 5-HT3 receptor agonists, citalopram dose greater than 20 mg/day, tolteridine and quinine.