## **Core Concept**
Captopril is an angiotensin-converting enzyme (ACE) inhibitor used primarily to treat hypertension and heart failure. ACE inhibitors work by blocking the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor. This leads to vasodilation and decreased blood pressure. However, this mechanism also results in various side effects.

## **Why the Correct Answer is Right**
The correct answer, , is associated with a side effect not typically related to captopril. Captopril commonly causes side effects like cough, hypotension, hyperkalemia, and renal impairment due to its mechanism of action.

## **Why Each Wrong Option is Incorrect**
* **Option A:** Captopril can cause a dry cough in some patients due to the increased levels of bradykinin, which is a known side effect of ACE inhibitors.
* **Option B:** can occur due to captopril's effect on reducing aldosterone levels, leading to increased potassium levels.
* **Option C:** is a recognized side effect, particularly notable in patients with bilateral renal artery stenosis or those with heart failure.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that ACE inhibitors like captopril are contraindicated in pregnancy, especially in the second and third trimesters, due to the risk of fetal harm. They can cause fetal hypotension, renal failure, and skull hypoplasia.

## **Correct Answer:** .