Trandolapril/verapamil

See Contraindications. For trandolapril: increased risk of angioedema with concomitant neprilysin inhibitor or mTOR inhibitor (eg, temsirolimus, sirolimus, everolimus). Dual inhibition of the renin-angiotensin system with ARBs, ACEIs, or aliskiren may increase risk of hypotension, hyperkalemia, renal function changes; monitor closely. Avoid concomitant aliskiren in renal impairment (CrCl <60mL/min). Excessive hypotension with diuretics. Hyperkalemia with K⁺ supplements, K⁺-sparing diuretics, salt substitutes. Potentiates antidiabetic agents. May be antagonized by, and renal toxicity potentiated by NSAIDs, including selective COX-2 inhibitors (monitor renal function in elderly and/or volume-depleted). Nitritoid reactions with concomitant injectable gold (eg, sodium aurothiomalate); rare. For verapamil: Potentiates alcohol, β-blockers, other antihypertensives, digitalis, ivabradine (avoid), lithium, theophylline, neuromuscular blockers, flecainide, carbamazepine, cyclosporine, sirolimus, tacrolimus, doxorubicin, tranquilizers/antidepressants (eg, buspirone, midazolam, almotriptan, imipramine), colchicine, dabigatran, flibanserin. Potentiated by grapefruit juice. Avoid disopyramide; quinidine in cardiomyopathy. Potentiated by CYP3A4 inhibitors (eg, erythromycin, ritonavir); antagonized by CYP3A4 inducers (eg, rifampin, St. John's wort). May potentiate statins; limit simvastatin dose to 10mg/day or lovastatin to 40mg/day. May need to reduce initial and maintenance dose for other CYP3A4 substrates (eg, atorvastatin). Inhalation anesthetics may potentiate cardiac depression. May increase bleeding with aspirin. Monitor theophylline, lithium levels.