Which medication, when combined with captopril, increases the risk for angina associated with hypotensive episodes?

Sildenafil, when used in combination with captopril, can increase the risk of angina due to the potential for hypotensive episodes. Captopril is an ace inhibitor that lowers blood pressure by preventing the conversion of angiotensin I to angiotensin II, leading to vasodilation. Sildenafil, a phosphodiesterase type 5 (PDE5) inhibitor, enhances the effects of nitric oxide by preventing the breakdown of cyclic GMP, which also results in vasodilation and can further lower blood pressure.

When these two medications are used together, the combined effects can significantly reduce blood pressure, leading to hypotension. In individuals who may already have compromised blood flow, particularly to the heart, this drop in blood pressure can precipitate angina, which is characterized by chest pain that arises when the heart doesn't receive enough blood and oxygen.

The other medications listed do not have the same potential for causing an additive hypotensive effect in conjunction with captopril. Amlodipine is a calcium channel blocker that can lower blood pressure, yet its mechanism and usual clinical considerations do not typically lead to the exacerbation of hypotensive events in the same manner as sildenafil with captopril. Metoprolol is a beta-blocker