Increased plasma conc w/ potent CYP3A4 inhibitors, including azole antifungals eg, fluconazole, itraconazole, ketoconazole, voriconazole; macrolide antibiotics eg, clarithromycin & erythromycin, HIV PIs eg, amprenavir, atazanavir, fosamprenavir, indinavir, nelfinavir, ritonavir & saquinavir; Ca antagonists eg, diltiazem & verapamil; amiodarone, aprepitant, nefazodone, telithromycin. Slight QT interval prolongation w/ fluconazole, ketoconazole, voriconazole, clarithromycin, erythromycin, amiodarone, telithromycin. May antagonize hypoprolactinaemia effect of bromocriptine. May suppress unwanted peripheral effect of bromocriptine & L-dopa. Enhanced gastric & small intestinal motive w/ SR & EC drug formulations. Molax susp: Lowered oral availability w/ antacids & antisecretory drugs.