Pharmacological classification: Nitrate
Therapeutic classification: muscle stimulant, vasodilator anti-angina
Consumption classification in pregnancy: Category C
Antianginal effect: Nitroglycerin reduces myocardial oxygen consumption by relaxing the smooth muscles of the vascular bed (arterial and venous). It also dilates the coronary arteries and redistributes blood flow to ischemic tissues. Possible effects This drug on coronary arteries and its systemic effects (which may be slightly altered by various forms of nitroglycerin) justify the use of this drug in the treatment of angina.
Dilation of vasodilators: Nitroglycerin dilates peripheral arteries, so intravenous injection of this drug is effective in lowering blood pressure during surgery and to control blood pressure in cases of hypertension before surgery. Since peripheral vasodilation Reduces the return of venous blood to the heart (preload), nitroglycerin is also used to treat pulmonary edema and congestive heart failure. Dilation of the arteries reduces arterial resistance (postload). Decreased left ventricular function helps the heart fail. The combination of these effects is effective in treating some patients with acute myocardial infarction.
Absorption: The time required to start the effect after intravenous injection is 1-2 minutes.
Distribution: Widespread throughout the body. About 60% of circulating drugs bind to plasma proteins.
Metabolism: Metabolized in the liver and serum to 3,1-glyceryl dinitrate, 2,1-glyceryl dinitrate and glyceryl mononitrate. Dinitrate metabolites have a mild vasodilating effect.
Excretion: Nitroglycerin metabolites are excreted in the urine. The elimination half-life of the drug is about 1-4 minutes. The duration of action of the drug after intravenous injection is 30 minutes.
Prevention of chronic angina attacks
• Treatment of acute angina, prevention of angina attacks or minimizing the risk of these attacks before stressful events that should be taken immediately
• Treatment of hypertension, congestive heart failure, angina
• Acute myocardial infarction
Stroke or cerebral hemorrhage (due to increased risk of intracranial pressure), severe anemia (nitrate ions can rapidly oxidize hemoglobin to methemoglobin), history of hypersensitivity with idiosyncratic reaction to nitrates, postural hypotension, hypotensive hypotension Blood or uncontrolled decrease in blood volume
A) Increased intracranial pressure (dilates meningeal arteries), open or closed angle glaucoma, dehydration or decreased systolic blood pressure (less than 90 mmHg) due to diuretics (due to antihypertensive effect) Nitroglycerin) in the first days after an acute myocardial infarction (may cause severe hypotension and tachycardia, but nitroglycerin has been shown to reduce myocardial ischemia and possibly reduce the spread of myocardial infarction to some extent).
B) There is a possibility of tolerance to the vascular and angina effects of drugs and the occurrence of cross-tolerance between nitrates and nitrites has been reported. The tolerance to this drug is due to high or continuous concentrations of the drug in plasma and often by oral administration, intravenous injection And topical application of the drug occurs. Tolerance is prevented by taking the least effective dose of the drug and also by taking the drug intermittently. Not taking this drug for 10-12 hours a day may prevent tolerance.
Concomitant use of alcohol-containing products, antihypertensive drugs or phenothiazines may also cause additional antihypertensive effects.
Concomitant use with ergot alkaloids may cause angina.
side effects :
Central nerves: headache (in some cases throbbing), dizziness, weakness, blurred vision
Cardiovascular: standing hypotension, tachycardia, flushing, palpitations, syncope
Skin: Dilation of cutaneous arteries, skin irritation (with topical application)
Gastrointestinal tract: nausea, vomiting
Topical: burning under the tongue, dry mouth
Other complications: Hypersensitivity reactions (skin rash, dermatitis), impotence, recurrent urination, rash, hypersensitivity reactions
Note: In case of skin rash, dermatitis, blurred vision or dry mouth, this drug should be discontinued.
How to store:
Keep away from light and at a temperature below 30 ° C. Protect from frost.