1 tablet contains the active substance: nitroglycerin 500 mcg
Peripheral vasodilator with a predominant effect on the venous vessels. Antianginal agent. The mechanism of action is associated with the release of the active substance nitric oxide in the smooth muscles of the blood vessels. Nitric oxide causes the activation of guanylate cyclase and increases the level of cGMP, which ultimately leads to relaxation of smooth muscle. Under the influence of glyceryl trinitrate, arterioles and precapillary sphincters relax to a lesser extent than large arteries and veins. This is partly due to reflex reactions, as well as the less intense formation of nitric oxide from the molecules of the active substance in the walls of arterioles. The action of nitroglycerin (glyceryl trinitrate) is associated mainly with a decrease in myocardial oxygen demand due to a decrease in preload (dilation of peripheral veins and a decrease in blood flow to the right atrium) and an afterload (decrease in OPS). Promotes the redistribution of coronary blood flow in the ischemic subendocardial areas of the myocardium. Increases tolerance to physical exertion in patients with coronary artery disease, angina. In heart failure, it promotes myocardial discharge, mainly due to a decrease in preload. Reduces pressure in the pulmonary circulation.
After ingestion is absorbed from the gastrointestinal tract, is the effect of the first passage through the liver. With sublingual use, this effect is absent, and the therapeutic concentration in the blood plasma is reached within a few minutes. Metabolized in the liver with the participation of nitrate reductase. Of the nitroglycerin metabolites, dinitro derivatives can cause pronounced vasodilation; it is possible that they determine the therapeutic effect of nitroglycerin (glyceryl trinitrate) when taken orally. Plasma protein binding is 60%. T1 / 2 after ingestion - 4 hours, with sublingual use - 20 minutes, after intravenous administration - 1-4 minutes. Excreted mainly by the kidneys.
Nitroglycerin spray is quickly and completely absorbed from the oral cavity into the systemic circulation.Bioavailability is 100% when taken sublingually, as it eliminates the "primary" hepatic degradation of the drug. Cmax in plasma is reached after 4 minutes. Communication with proteins of a blood plasma makes 60%. It is rapidly metabolized with the participation of nitrate reductase, with the formation of dii mononitrates (only isosorbide-5-mononitrate is active), the final metabolite glycerin. Excreted by the kidneys as metabolites. Total clearance is 25-30 l / min. After taking the drug under the tongue, T1 / 2 from plasma is 2.5-4.4 minutes. Circulating nitroglycerin is strongly associated with red blood cells and accumulates in the walls of blood vessels. The main route of excretion of nitroglycerin is the extraction of metabolites with urine. less than 1% of the dose is excreted.
Hypersensitivity to nitroglycerin, to auxiliary components of the drug, nitrates. Cerebral ischemia, cardiac tamponade, hypertrophic obstructive cardiomyopathy, simultaneous use with sildenafil and other phosphodiesterase inhibitors, arterial hypotension (systolic blood pressure (BP) below 100 mm Hg., Diastolic blood pressure below 60 mm Hg.), Elevation of blood pressure below 100 mm Hg, diastolic blood pressure below 60 mm of mercury. (including with hemorrhagic stroke, after a recent head injury), angle-closure glaucoma with high intraocular pressure. Vascular collapse, shock, acute myocardial infarction, accompanied by a decrease in the filling pressure of the left ventricle (isolated mitral stenosis, constructive pericarditis), bradycardia (less than 50 beats / min).
Since the cardiovascular system: dizziness, headache, tachycardia, skin hyperemia, fever, arterial hypotension; rarely (especially in overdose) - collapse, cyanosis. On the part of the digestive system: nausea, vomiting. From the side of the central nervous system: rarely (especially in case of overdose) - anxiety, psychotic reactions.
Use during pregnancy and lactation
The use of nitroglycerin (glyceryl trinitrate) during pregnancy and lactation (breastfeeding) is possible only in cases where the intended benefits to the mother outweigh the potential risk to the fetus or infant.
Dosage and administration
With angina, nitroglycerin should be taken sublingually immediately after the onset of an attack. The usual dose of the drug - 1 tablet, for many patients with stable angina pectoris and a smaller dose is effective. Therefore, if the pain quickly passes, it is recommended to spit out the rest of the pill that did not have time to completely dissolve. In the absence of antianginal action within the first 5 minutes, you must take another 1 tablet. In the absence of a therapeutic effect after taking 2-3 pills, you should immediately call a doctor (the likelihood of myocardial infarction)! Nitroglycerin is valid for 30 minutes. With frequent attacks of angina, it is advisable to prescribe prolonged nіtroglіtserinovogo series. However, if an angina attack develops during treatment with prolonged nitrates, nitroglycerin should be used to relieve an acute attack. Tolerance to sublingual forms of nitroglycerin rarely develops, but when it occurs in some patients, the dose of the drug should be gradually increased, bringing it to 2-3 pills.
Adverse reactions of the drug Nitroglycerin: From the side of the central nervous system, blurred vision, headache, dizziness and feeling of weakness, anxiety, psychotic reactions, lethargy, disorientation. including orthostatic collapse, cyanosis, pallor, methemoglobinemia. Nausea, vomiting, dry mouth, abdominal pain, diarrhea are possible on the digestive tract. On the part of the immune system system allergic reactions, including skin rashes, itching. anaphylactic shock. Other excitability, visual impairment, exacerbation of glaucoma, hypothermia. Sometimes, with a sudden decrease in blood pressure, there may be an increase in the symptoms of angina pectoris (paradoxical "nitrate" reactions).
Interaction with other drugs
With simultaneous use with vasodilators, ACE inhibitors, calcium channel blockers, beta-blockers, diuretics, tricyclic antidepressants, MAO inhibitors, ethanol, ethanol-containing drugs may increase the hypotensive effect of glyceryl trinitrate. With simultaneous use with beta-blockers, calcium channel blockers increases antianginal action.With simultaneous use with sympathomimetics, the antianginal effect of glyceryl trinitrate may be reduced, which, in turn, may reduce the pressor effect of sympathomimetics (as a result, arterial hypotension is possible). With the simultaneous use of agents with anticholinergic activity (including tricyclic antidepressants, disopyramide), hyposalivation and dry mouth develop. There is limited evidence that acetylsalicylic acid, used as an analgesic, increases the concentration of nitroglycerin (glyceryl trinitrate) in blood plasma. This may be accompanied by increased hypotensive effect and headaches. In a number of studies, a reduction in the vasodilating effect of nitroglycerin (glyceryl trinitrate) was observed during long-term therapy with acetylsalicylic acid. It is believed that it is possible to enhance the antiplatelet effect of acetylsalicylic acid on the background of the use of nitroglycerin (glyceryl trinitrate). With simultaneous use of nitroglycerin decreases the effect of acetylcholine, histamine, norepinephrine. On the background of intravenous injection of nitroglycerin, a decrease in the anticoagulant effect of heparin is possible. With simultaneous use, it is possible to increase the bioavailability of dihydroergotamine and reduce the antianginal effect of nitroglycerin (glyceryl trinitrate). With simultaneous use with procainamide may increase the hypotensive effect and the development of collapse. With simultaneous use with rizatriptan, sumatriptan increases the risk of developing spasm of the coronary arteries; with sildenafil - the risk of severe arterial hypotension and myocardial infarction; with quinidine - orthostatic collapse is possible; with ethanol - severe weakness and dizziness.
It is used with caution in patients with severe cerebral atherosclerosis, impaired cerebral circulation, with a tendency to orthostatic hypotension, with severe anemia, in elderly patients, as well as with hypovolemia and pronounced impaired function of the liver and kidneys (parenteral). With prolonged use may develop tolerance to the action of nitrates.To prevent the occurrence of tolerance, it is recommended to observe a 10-12 hour break in their use during each 24-hour cycle. If the cutaneous use of nitroglycerin (glyceryl trinitrate) causes angina, it should be stopped by taking glyceryl trinitrate under the tongue. During the period of treatment to prevent the use of alcohol. Impact on the ability to drive vehicles and control mechanisms: Glyceryl trinitrate can reduce the speed of psychomotor reactions that should be considered when driving vehicles or doing other potentially dangerous activities.