Glycerylnitrat (Glyceryl Trinitrate)

Glycerylnitrat is indicated for the rapid relief of chest pain and for the management of several acute cardiovascular emergencies. It is administered intravenously in controlled clinical settings.

• Acute angina pectoris unresponsive to oral nitrates.
• Acute decompensated heart failure with pulmonary congestion.
• Hypertensive emergencies requiring immediate blood pressure reduction.
• Peri‑operative myocardial ischemia prophylaxis.
• Severe coronary artery spasm (Prinzmetal angina).

The safety profile of Glycerylnitrat includes both frequently observed and less common adverse reactions, which are generally related to its vasodilatory action.

Common

• Headache, often described as throbbing.
• Flushing or warmth of the face and neck.
• Hypotension leading to dizziness.
• Tachycardia or reflex heart rate increase.
• Nausea or mild vomiting.

Serious

• Severe hypotension causing syncope.
• Methemoglobinemia, a rare blood disorder.
• Acute myocardial infarction in susceptible patients.
• Life‑threatening arrhythmias.
• Severe allergic reactions such as anaphylaxis.

Before using Glycerylnitrat, clinicians should assess patient history and monitor vital signs closely during therapy.

• Avoid use in patients with known hypersensitivity to nitrates.
• Use cautiously in patients with severe anemia or increased intracranial pressure.
• Monitor blood pressure continuously to detect excessive drops.
• Assess for concurrent use of phosphodiesterase‑5 inhibitors, which can amplify hypotensive effects.
• Adjust dosage in patients with hepatic or renal impairment.
• Educate patients about the risk of tolerance with prolonged exposure.

Glycerylnitrat may interact with several drug classes, influencing its efficacy and safety.

Avoid

• Phosphodiesterase‑5 inhibitors (e.g., sildenafil, tadalafil) due to risk of profound hypotension.
• Other potent vasodilators such as hydralazine or other nitrates, which can cause additive blood pressure lowering.
• Certain antihypertensive agents (e.g., ACE inhibitors, beta‑blockers) when combined may require close monitoring.

Use with caution

• Diuretics, especially loop diuretics, which may exacerbate volume depletion.
• Alcohol, which can enhance vasodilatory effects.
• Anticoagulants, as hypotension may increase bleeding risk.
• Drugs that affect hepatic metabolism (e.g., CYP3A4 inhibitors) may alter nitrate clearance.