Is 5 Mono (Isosorbide Mononitrate)

Isosorbide Mononitrate is employed in the management of coronary artery disease and related cardiovascular conditions.

• Angina pectoris: reduces the frequency and severity of chest pain episodes.
• Chronic heart failure: improves exercise tolerance and alleviates dyspnoea.
• Ischemic heart disease: helps control myocardial oxygen demand and prevents anginal attacks.

• Isosorbide Mononitrate is metabolized to release nitric oxide, which activates guanylate cyclase in vascular smooth muscle. The resulting increase in cyclic GMP causes relaxation of arterial and venous vessels, lowering preload and afterload, and thereby decreasing myocardial oxygen consumption.

Common Side Effects

• Headache: mild to moderate, often transient.
• Dizziness or light‑headedness, especially on standing.
• Flushing of the face or neck.
• Hypotension: mild reduction in blood pressure.
• Nausea or abdominal discomfort.
• Palpitations or tachycardia.

Serious or Rare Side Effects

• Severe hypotension leading to syncope.
• Allergic reactions such as rash, pruritus, or angio‑edema.
• Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Myocardial infarction (rare, usually in patients with pre‑existing coronary disease).
• Life‑threatening arrhythmias.
• Methemoglobinemia (very rare).

Before initiating therapy, consider the following precautions:

• Concomitant nitrates: avoid combined use to prevent profound hypotension.
• Phosphodiesterase‑5 inhibitors: do not co‑administer due to risk of severe blood pressure fall.
• Renal impairment: dose may need adjustment; monitor renal function.
• Hepatic disease: use with caution; monitor liver enzymes.
• Abrupt discontinuation: taper dose to reduce rebound angina.
• Store at below 25°C: keep in the original container, protect from moisture and direct sunlight.

Isosorbide Mononitrate may interact with several drug classes.

Major Interactions (Avoid)

• Other nitrates (e.g., nitroglycerin, isosorbide dinitrate): risk of additive hypotension.
• Phosphodiesterase‑5 inhibitors (e.g., sildenafil, tadalafil): can cause dangerous blood pressure drops.
• Potent antihypertensives (e.g., clonidine, hydralazine): may lead to excessive vasodilation.

Moderate Interactions (Monitor Closely)

• Diuretics: may enhance hypotensive effect; monitor blood pressure.
• ACE inhibitors or ARBs: combined effect on blood pressure requires observation.
• Beta‑blockers and calcium‑channel blockers: monitor for additive cardiovascular effects.