Nitroglycerin

What it is and how it works

Mechanism of Action Nitroglycerin forms free radical nitric oxide (NO) which activates guanylate cyclase, resulting in an increase of guanosine 3'5' monophosphate (cyclic GMP) in smooth muscle and other tissues. These events lead to dephosphorylation of myosin light chains, which regulate the contractile state in smooth muscle, and result in vasodilatation.

Indications

Nitroglycerin sublingual tablets are indicated for the acute relief of an attack or acute prophylaxis of angina pectoris due to coronary artery disease. Nitroglycerin sublingual tablets are a nitrate vasodilator indicated for relief of an attack or prophylaxis of angina pectoris due to coronary artery disease.

Dosage and administration (summary)

Administer one tablet under the tongue or in the buccal pouch at the first sign of an acute anginal attack. Allow tablet to dissolve without swallowing. One additional tablet may be administered every 5 minutes until relief is obtained. No more than three tablets are recommended within a 15-minute period. If the pain persists after a total of 3 tablets in a 15-minute period, or if the pain is different than is typically experienced, seek prompt medical attention. Nitroglycerin sublingual tablets may be used prophylactically 5 to 10 minutes prior to engaging in activities that might precipitate an acute attack.

Contraindications

• Use of phosphodiesterase type 5 (PDE-5) inhibitors, such as avanafil, sildenafil, tadalafil, or vardenafil, or soluble guanylate cyclase (sGC) stimulators. ( 4.1 , 7.1 ) • Severe anemia • Increased intracranial pressure • Hypersensitivity to nitroglycerin or to other nitrates or nitrites or any excipient • Circulatory failure and shock PDE-5-Inhibitors and sGC-Stimulators Do not use nitroglycerin sublingual tablets in patients who are taking PDE-5 Inhibitors, such as avanafil, sildenafil, tada…

Warnings and precautions

• Tolerance: Excessive use may lead to tolerance. • Hypotension: Severe hypotension may occur. Tolerance Excessive use may lead to the development of tolerance. Only the smallest dose required for effective relief of the acute angina attack should be used. A decrease in therapeutic effect of sublingual nitroglycerin may result from use of long-acting nitrates.

Pregnancy

Pregnancy Risk Summary Limited published data on the use of nitroglycerin are insufficient to determine a drug associated risk of major birth defects or miscarriage. In animal reproduction studies, there were no adverse developmental effects when nitroglycerin was administered intravenously to rabbits or intraperitoneally to rats during organogenes…

Storage and supply

Nitroglycerin Sublingual Tablets are supplied as white, round, flat-faced tablets in 3 strengths (0.3 mg, 0.4 mg, and 0.6 mg) in bottles containing 100 tablets each, with color-coded labels, and in color-coded Patient Convenience Packages of 4 bottles of 25 tablets each. 0.3 mg: Coded “N” on one side and “3” on the other.

Source: Nitroglycerin (Nitroglycerin) — US FDA prescribing information, 2024-10-15, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.