Mononitrato De Isosorbida Normon (Isosorbide Mononitrate)

Isosorbide Mononitrate belongs to the organic nitrate class and is used in the management of coronary artery disease‑related chest pain.

• Angina pectoris: reduces the frequency and severity of chest pain episodes.
• Chronic stable angina: improves exercise tolerance and delays onset of pain.
• Ischemic heart disease: decreases myocardial oxygen demand by vasodilation of coronary vessels.

• Isosorbide Mononitrate is metabolized to release nitric oxide, which activates guanylate cyclase in vascular smooth muscle. The resulting increase in cyclic GMP leads to relaxation of arterial and venous smooth muscle, producing systemic vasodilation, reduced preload and afterload, and consequently lower myocardial oxygen consumption.

Isosorbide Mononitrate may cause a range of adverse reactions, most of which are dose‑related and reversible.

Common Side Effects

• Headache: throbbing pain often occurring shortly after dosing.
• Dizziness or light‑headedness: related to blood pressure lowering.
• Flushing: warm sensation and reddening of skin.
• Nausea: mild gastrointestinal upset.
• Palpitations: awareness of heartbeat.

Serious or Rare Side Effects

• Severe hypotension: marked drop in blood pressure requiring medical attention.
• Syncope: sudden loss of consciousness.
• Myocardial infarction: rare but possible in susceptible individuals.
• Life‑threatening arrhythmias: irregular heart rhythms.
• Allergic reactions: rash, itching, or swelling.
• Stevens‑Johnson syndrome: severe skin reaction, extremely rare.

Before initiating therapy, clinicians should evaluate cardiovascular status and consider patient‑specific factors.

• Assess blood pressure: ensure baseline values are adequate to tolerate vasodilation.
• Review cardiac history: avoid in patients with recent myocardial infarction or unstable angina.
• Monitor for drug tolerance: efficacy may diminish over time.
• Caution in hepatic or renal impairment: dose adjustments may be required.
• Avoid abrupt discontinuation: taper to prevent rebound angina.
• Store at ambient temperature below 25°C: keep in the original pack, protect from moisture.

Isosorbide Mononitrate can interact with several medication classes, altering its safety profile.

Major Interactions (Avoid)

• Sildenafil and other PDE5 inhibitors: risk of severe hypotension.
• Concomitant organic nitrates (e.g., nitroglycerin): additive vasodilatory effect.
• Alcohol: may potentiate blood pressure lowering.

Moderate Interactions (Monitor Closely)

• Antihypertensive agents: possible need for dose reduction.
• Diuretics: increased likelihood of orthostatic hypotension.
• Beta‑blockers: monitor heart rate and blood pressure for bradycardia.