**Question:** Which antihypertensive is not given in pregnancy -

A. ACE inhibitors (e.g., ramipril)
B. Angiotensin II receptor blockers (e.g., losartan)
C. Calcium channel blockers (e.g., amlodipine)
D. Diuretics (e.g., furosemide)

**Correct Answer: ACE inhibitors (e.g., ramipril)**

**Core Concept:** Pregnancy-induced hypertension (PIH) is a form of hypertension that develops during pregnancy. It is associated with increased risk of maternal and fetal complications, thus prompt diagnosis and management are essential.

**Why the Correct Answer is Right:** ACE inhibitors are not recommended for use in pregnancy due to potential harm to the developing fetus. Angiotensin-converting enzyme (ACE) inhibitors work by blocking the conversion of angiotensin I to angiotensin II, which results in vasodilation and reduced aldosterone secretion. This leads to a decrease in blood pressure. However, these medications can cause severe fetal malformations and growth retardation, leading to the avoidance of their use in pregnancy.

**Why Each Wrong Option is Incorrect:**

**Option B (Angiotensin II receptor blockers):** These medications work by blocking the binding of angiotensin II to its receptors, thus preventing vasoconstriction and aldosterone secretion. They are generally safe in pregnancy and are often used in cases of preeclampsia (a severe form of PIH).

**Option C (Calcium channel blockers):** Calcium channel blockers, like ACE inhibitors, work by reducing vasoconstriction and thus lowering blood pressure. However, unlike ACE inhibitors, calcium channel blockers are considered safe in pregnancy, as they do not pose significant risks to the developing fetus.

**Option D (Diuretics):** Diuretics increase urine output, leading to salt and water loss, which reduces blood volume and subsequently blood pressure. They are generally safe in pregnancy, but the choice of specific diuretic (e.g., furosemide) is crucial as some diuretics (e.g., chlorothiazide) are contraindicated during pregnancy due to potential fetal harm.

**Clinical Pearl:** When managing hypertension in pregnancy, the choice of antihypertensive medication depends on the severity of hypertension and the presence of complications like preeclampsia. ACE inhibitors and calcium channel blockers should be avoided unless used specifically for preeclampsia. Diuretics can be used, but the choice of medication (e.g., furosemide) should be cautious to avoid potential fetal harm.