Contraindicated w/ QTc-prolonging medicinal products, anti-arrhythmics class IA (eg, disopyramide, hydroquinidine, quinidine), anti-arrhythmics class III (eg, amiodarone, dofetilide, dronedarone, ibutilide, sotalol), certain anti-psychotics (eg, haloperidol, pimozide, sertindole), certain anti-depressants (eg, citalopram, escitalopram), certain antibiotics (eg, erythromycin, levofloxacin, moxifloxacin, spiramycin), certain antifungals (eg, pentamidine), certain antimalarials (halofantrine, lumefantrine), certain GI medicines (eg, cisapride, dolasetron, prucalopride), certain antihistaminics (eg, mequitazine, mizolastine), certain medicines used in cancer (eg, toremifene, vandetanib, vincamine), certain other medicines (eg, bepridil, diphemanil, methadone), apomorphine; potent CYP3A4 inhibitors ie, PIs, systemic azole antifungals, some macrolides (erythromycin, clarithromycin, telithromycin). Not recommended w/ moderate CYP3A4 inhibitors ie, diltiazem, verapamil & some macrolides. Caution w/ bradycardia & hypokalaemia-inducing drugs; macrolides involved in QT-interval prolongation eg, azithromycin & roxithromycin. Increased plasma levels of levodopa.