Glytrin (Glyceryl Trinitrate)

Glytrin is indicated for the treatment and prevention of angina pectoris related to coronary artery disease.

• Relief of acute angina attacks when chest pain occurs.
• Short‑term prophylaxis before physical exertion or emotional stress that may trigger angina.
• Use in emergency settings when rapid onset of action is required.
• Adjunct therapy in patients already receiving other anti‑anginal agents.
• Management of angina in patients who cannot tolerate oral nitrates.
• Treatment of angina in patients undergoing diagnostic procedures that may provoke myocardial ischemia.

The most frequently reported effects of sublingual glyceryl trinitrate are related to its vasodilating action, while rare but serious reactions may also occur.

Common

• Headache, often described as throbbing.
• Flushing or warmth in the face and neck.
• Dizziness or light‑headedness, especially when standing quickly.
• Low blood pressure (hypotension) causing faintness.
• Rapid heart rate (reflex tachycardia).
• Nausea or mild vomiting.
• Dry mouth.

Serious

• Severe hypotension leading to syncope.
• Chest pain that worsens or does not improve.
• Allergic reactions such as rash, itching, or swelling.
• Methemoglobinemia (rare).
• Persistent tachycardia with hemodynamic instability.
• Cardiac arrhythmias.

Before using Glytrin, certain precautions should be considered to minimize risks and ensure safe therapy.

• Patients with known hypersensitivity to nitrates should avoid Glytrin.
• Use caution in individuals with low blood pressure or a history of hypotension.
• Assess for severe anemia or increased intracranial pressure before administration.
• Evaluate cardiac status in patients with recent myocardial infarction or unstable angina.
• Avoid abrupt discontinuation in patients on long‑term nitrate therapy to prevent rebound angina.
• Use with caution in patients taking phosphodiesterase‑5 inhibitors due to risk of profound hypotension.
• Pregnancy and breastfeeding status should be discussed with a healthcare professional.

Glytrin can interact with several medications; recognizing these interactions helps prevent adverse effects.

Avoid

• Concomitant use of phosphodiesterase‑5 inhibitors (e.g., sildenafil, tadalafil) due to risk of severe hypotension.
• Combined therapy with other potent vasodilators such as hydralazine or calcium‑channel blockers may cause excessive blood pressure drop.
• Use with other nitrate preparations (e.g., isosorbide dinitrate) should be avoided to prevent additive effects.

Use with caution

• Beta‑blockers may mask tachycardia, requiring close monitoring.
• Certain antihypertensive agents (e.g., ACE inhibitors, ARBs) may enhance hypotensive response.
• Alcohol can potentiate vasodilatory effects, increasing dizziness.
• Diuretics may exacerbate low blood pressure when used together.