Monoket Od (Isosorbide Mononitrate)

Isosorbide Mononitrate is used in the management of coronary artery disease‑related chest pain and works within the anti‑anginal drug family.

• Chronic stable angina: reduces the frequency of anginal attacks and improves exercise tolerance.
• Effort‑induced angina: lessens chest pain triggered by physical activity.
• Angina prophylaxis: provides long‑term prevention of angina episodes.

• 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, leading to vasodilation, reduced preload and afterload, and enhanced myocardial oxygen delivery.

Isosorbide Mononitrate may cause a range of adverse reactions, from mild to serious.

Common Side Effects

• Headache: throbbing pain often occurring shortly after dosing.
• Dizziness: light‑headed sensation, especially when standing quickly.
• Flushing: warm sensation and reddening of the skin.
• Hypotension: low blood pressure that may cause faintness.
• Nausea: upset stomach or feeling of queasiness.
• Palpitations: awareness of irregular or rapid heartbeats.

Serious or Rare Side Effects

• Severe hypotension: marked drop in blood pressure requiring medical attention.
• Syncope: sudden loss of consciousness.
• Myocardial infarction (rare): heart attack symptoms.
• Allergic reaction: rash, itching, swelling, or difficulty breathing.
• Stevens‑Johnson syndrome: severe skin blistering and detachment.

Before initiating therapy, clinicians should evaluate patient‑specific factors and monitor for potential complications.

• Cardiovascular assessment: confirm stable angina diagnosis and baseline blood pressure.
• Blood pressure monitoring: check regularly, especially after dose changes.
• Avoid abrupt discontinuation: taper to prevent rebound angina.
• Hepatic impairment: use with caution in patients with liver dysfunction.
• Concomitant PDE‑5 inhibitors: avoid due to risk of profound hypotension.
• Store at ambient temperature: keep in the original pack, protect from moisture.

Isosorbide Mononitrate can interact with several drug classes; awareness helps prevent adverse events.

Major Interactions (Avoid)

• Sildenafil, tadalafil, or other PDE‑5 inhibitors: may cause severe hypotension.
• Other nitrates (e.g., nitroglycerin, isosorbide dinitrate): additive vasodilatory effect.
• Sodium nitroprusside: excessive blood pressure lowering.

Moderate Interactions (Monitor Closely)

• Antihypertensives (ACE inhibitors, beta‑blockers): may enhance blood pressure reduction.
• Diuretics: increase risk of dehydration and hypotension.
• Alcohol: can potentiate vasodilatory effects and dizziness.