Isorem (Isosorbide Dinitrate)

Isosorbide dinitrate is used in the cardiovascular therapeutic class to relieve myocardial ischemia and support cardiac function.

• Angina pectoris: decreases the frequency and severity of chest pain episodes by lowering cardiac workload and reduces the need for short‑acting nitrates.
• Chronic heart failure: improves symptoms and exercise capacity by reducing preload and afterload and may lessen hospital admissions.
• Prophylaxis of angina: maintains stable coronary blood flow to prevent angina attacks during physical exertion, especially in patients with predictable triggers.

• Isosorbide dinitrate is metabolized to release nitric oxide, which activates soluble guanylate cyclase in vascular smooth‑muscle cells. The resulting increase in cyclic guanosine monophosphate causes relaxation of arterial and venous smooth muscle, producing vasodilation. This reduces both preload and afterload, decreasing myocardial oxygen consumption and improving coronary blood flow, thereby alleviating ischemic chest pain. The effect is dose‑dependent and reversible upon drug discontinuation.

Isosorbide dinitrate may be associated with several adverse reactions, ranging from frequent to rare.

Common Side Effects

• Headache: throbbing pain often occurring shortly after dosing, may be relieved by analgesics.
• Dizziness or light‑headedness: due to orthostatic hypotension, especially when standing quickly.
• Flushing: warm sensation and reddening of the skin, typically transient.
• Nausea: mild gastrointestinal upset that usually resolves without treatment.
• Hypotension: mild drop in blood pressure causing fatigue or weakness.
• Palpitations: awareness of heartbeat, sometimes accompanied by mild fluttering.

Serious or Rare Side Effects

• Severe hypotension: marked drop in blood pressure leading to fainting, dizziness, or shock.
• Reflex tachycardia: rapid heart rate in response to vasodilation, may cause palpitations.
• Methemoglobinemia: abnormal hemoglobin causing cyanosis and reduced oxygen delivery (very rare).
• Allergic reactions: rash, itching, or anaphylaxis requiring immediate medical attention.
• Chest pain worsening: may indicate myocardial ischemia and necessitates urgent evaluation.

When prescribing isosorbide dinitrate, several precautions should be observed to ensure safe use.

• Assess cardiovascular status: evaluate blood pressure and heart