In MONA therapy, which medication is used to vasodilate and relieve chest pain?

• A. Morphine
• B. Oxygen
• C. Aspirin
• D. Nitroglycerin

Answer: (D)

Nitroglycerin provides vasodilation that directly relieves chest pain in MONA therapy. It works by releasing nitric oxide, which relaxes vascular smooth muscle. This causes venodilation that lowers preload and reduces left ventricular wall stress, thereby decreasing myocardial oxygen demand. It also dilates coronary arteries, which can improve blood flow to the ischemic heart muscle. The result is rapid relief of angina symptoms, especially when given sublingually or by IV if needed. While morphine offers analgesia and some venodilation, oxygen helps only if the patient is hypoxemic, and aspirin prevents further clot formation—nitroglycerin is the agent best suited to quickly dilate vessels and ease chest pain.