Which antihypertensive medication should be avoided in patients with asthma?

• A. Diltiazem
• B. Propranolol
• C. Amlodipine
• D. Metolazone

Answer: (B)

Nonselective beta-blockers should be avoided in asthma because they block beta-2 receptors on bronchial smooth muscle. This blunts the natural beta-2–mediated bronchodilation and can cause bronchoconstriction, potentially triggering or worsening asthma symptoms. Propranolol is a classic example of a nonselective beta-blocker, which is why it’s the drug to avoid in patients with asthma.

If a beta-blocker is ever considered for a hypertensive patient with asthma, a cardioselective agent that mainly blocks beta-1 receptors (at the lowest effective dose) may be used with caution and close monitoring. The other listed meds act through different mechanisms—calcium channel blockers or a diuretic—and do not directly promote bronchoconstriction, so they don’t carry the same asthma risk.