Uses

Indicated for the prevention and treatment of angina pectoris due to coronary artery disease. Not suitable for aborting an acute anginal attack due to slow onset of action. Extended-release formulations are used for once-daily prophylaxis.

Do not use if

Contraindicated in patients with known hypersensitivity to isosorbide mononitrate, concurrent use of phosphodiesterase inhibitors (sildenafil, tadalafil, vardenafil), severe anemia, increased intracranial pressure, and constrictive pericarditis.

Side effects

Headache is the most frequent side effect, particularly at treatment initiation, and tends to diminish with continued use. Other effects include dizziness, hypotension, flushing, and reflex tachycardia. Severe hypotension may occur, especially with concurrent use of phosphodiesterase inhibitors.

Warnings

Concurrent use with phosphodiesterase inhibitors (e.g., sildenafil) can cause severe hypotension; concomitant use is contraindicated. Tolerance may develop with continuous nitrate therapy; a nitrate-free interval is recommended. Abrupt withdrawal may cause rebound angina.

How it works

Isosorbide mononitrate is the major active metabolite of isosorbide dinitrate. It relaxes vascular smooth muscle via release of nitric oxide, leading to venodilation and arterial dilation. This reduces cardiac preload and afterload, decreasing myocardial oxygen demand.

Storage

Store at controlled room temperature, 20–25°C (68–77°F). Keep in a tightly closed container. Protect from moisture and heat.