Pharmacology · single question
A female (56 y/o) with hypertension, hyperlipidemia, and asthma takes albuterol, atorvastatin, and metoprolol. What is the MOA of the medication used to CONTROL HYPERTENSION?
Show answer and explanation
Correct answer: A. Competitively inhibits β1 receptors
- A. Correct. METOPROLOL (the hypertension medication in this patient) COMPETITIVELY INHIBITS β1 (beta-1) ADRENERGIC RECEPTORS on the heart. β1 blockade reduces heart rate, myocardial contractility, and cardiac output — lowering blood pressure. It is cardioselective, minimizing β2 effects on bronchi (important since the patient has asthma).
- B. Incorrect. Calcium channel blockade is the MOA of amlodipine, verapamil, diltiazem — not metoprolol.
- C. Incorrect. Nitric oxide release is the MOA of organic nitrates (nitroglycerin) — not metoprolol.
- D. Incorrect. β2 receptor blockade would cause bronchoconstriction — metoprolol is cardioSELECTIVE and primarily blocks β1. Non-selective beta-blockers block β2, but metoprolol preferentially blocks β1.