<qa>  What is the CYP3A4 inhibitor?- Concomitant use of monoamine oxidase inhibitors MAOIs, cimetidine, lithium, theophylline, digoxin, sumatriptan, warfarin, carbamazepine, triazolam, ketoconazole, CYP3A4 and 2C19 inhibitors, and metoprolol. 