Glytrin (Glyceryl Trinitrate)

Glytrin is indicated for the acute relief of angina pectoris and for the prophylactic management of angina episodes in patients with coronary artery disease.

• Treatment of an acute angina attack when rapid onset of action is required.
• Prevention of angina episodes before physical exertion or emotional stress.
• Adjunct therapy in patients undergoing diagnostic cardiac stress testing.
• Use in combination with other anti‑anginal agents when monotherapy is insufficient.
• Management of angina in patients with known nitrate tolerance, under medical supervision.

The most frequently reported effects of sublingual glyceryl trinitrate are related to its vasodilatory action, while rare but serious reactions may require immediate medical attention.

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.

Serious

• Severe hypotension with syncope.
• Rapid heart rate (tachycardia) or irregular rhythm.
• Allergic reactions such as rash, itching, or swelling of the face and throat.

Because Glytrin produces potent vasodilation, several precautions should be observed before prescribing or using the medication.

• Assess blood pressure; avoid use in patients with severe hypotension.
• Review history of recent phosphodiesterase‑5 inhibitor use, as combined effect can cause dangerous hypotension.
• Caution in patients with hypertrophic cardiomyopathy or aortic stenosis.
• Monitor for signs of nitrate tolerance with long‑term therapy.
• Advise patients to sit or lie down after administration to reduce risk of fainting.
• Pregnant or breastfeeding women should use only if the potential benefit outweighs risk.

Glytrin can interact with several medicines, altering its efficacy or increasing the risk of adverse effects.

Avoid

• Phosphodiesterase‑5 inhibitors (e.g., sildenafil, tadalafil) – may cause profound hypotension.
• Other nitrate preparations – risk of additive vasodilation and severe low blood pressure.
• Guanylate cyclase stimulators – can amplify nitric oxide effects.

Use with caution

• Antihypertensive agents such as beta‑blockers, calcium channel blockers, or ACE inhibitors – monitor blood pressure.
• Alcohol – may enhance vasodilatory side effects like dizziness.
• Diuretics – may increase risk of dehydration‑related hypotension.