diltiazem + nifedipine + verapamil

This is a combination of three calcium channel blockers (CCBs): diltiazem, nifedipine, and verapamil. All three are small molecule drugs that inhibit the influx of calcium ions through L-type calcium channels in cardiac and vascular smooth muscle. Diltiazem and verapamil are classified as nondihydropyridine CCBs, while nifedipine is a dihydropyridine CCB. The combination aims to leverage their complementary pharmacological effects for enhanced antihypertensive or antianginal efficacy. Diltiazem and verapamil also inhibit CYP3A-mediated metabolism, which can increase plasma concentrations of nifedipine when used together[2][3][4]. Clinical studies have shown that dual combinations (e.g., diltiazem + nifedipine or verapamil + nifedipine) can provide greater blood pressure reduction than monotherapy[3][5], but there is limited evidence on the safety or efficacy of using all three agents simultaneously due to potential for additive adverse effects such as bradycardia, hypotension, edema, headache, dizziness, and constipation[2][4][6]. This triple combination would be considered highly unconventional in clinical practice.