Serotonin syndrome w/ other serotonergic drugs. Increased sedating effect of benzodiazepines & other sedatives (eg, antipsychotics, H
1-antagonists, opioids). Increased CNS depressant effect of alcohol. Increased INR w/ warfarin. Risk of QT prolongation &/or ventricular arrhythmia w/ drugs prolonging QTc interval. Decreased plasma conc w/ carbamazepine, phenytoin, CYP3A4 inhibitors. Increased peak plasma levels & AUC w/ ketoconazole. Increased plasma conc w/ cimetidine. HIV PIs, azole antifungals, erythromycin or nefazodone.