(±) -1- [4- (2-Methoxyethyl) phenoxy] -3 – [(1-methylethyl) amino] -2-propanol (in the form of tartrate or succinate). Metoprolol tartrate: a white, practically odorless crystalline powder, soluble in water, methylene chloride, chloroform and alcohol, slightly soluble in acetone, insoluble in ether. Metoprolol succinate: a white crystalline powder, easily soluble in water, soluble in methanol, sparingly soluble in ethanol, slightly soluble in dichloromethane and 2-propanol, practically insoluble in ethyl acetate, acetone, diethyl ether and heptane.
Metoprolol acts primarily on the beta1-adrenoreceptors of the heart. It has antianginal, antihypertensive and antiarrhythmic effects. Reduces the automatism of the sinus node, reduces the heart rate, slows down the atrioventricular conductivity, reduces myocardial contractility and excitability, cardiac output, myocardial need for oxygen. Suppresses the stimulating effect of catecholamines on the heart during physical and psychoemotional stress.
The antihypertensive effect develops gradually and stabilizes by the end of the 2nd week of the course of the drug. With exertional angina, Metoprolol reduces the frequency and severity of seizures. Normalizes heart rhythm with supraventricular tachycardia and atrial fibrillation. While receiving metoprolol in patients with myocardial infarction, as a result of limiting the infarction zone and reducing the risk of developing fatal arrhythmias, mortality and the possibility of a recurrence of myocardial infarction are reduced. When used in moderate therapeutic doses, it has a less pronounced effect on the smooth muscles of the bronchi and peripheral arteries than non-selective beta-blockers.
Indications for use
Arterial hypertension tachycardia), hypertrophic cardiomyopathy, mitral valve prolapse, myocardial infarction (prevention and treatment), migraine (prevention), thyrot ksikoz (complex therapy); treatment of akathisia caused by neuroleptics.
Mode of application
Inside, with food or immediately after a meal, tablets can be divided in half, but not chewed and washed down with liquid, for long-acting dosage forms, swallow whole, do not crush, do not break (except metoprolol succinate and tartrate), do not chew. In hypertension, the average dose is 100-150 mg / day in 1-2 doses, if necessary – 200 mg / day. With angina – 50 mg 2-3 times a day. In hyperkinetic cardiac syndrome (in
At the beginning of therapy, weakness, fatigue, dizziness, headache, muscle cramps, feeling of cold and paresthesia in the limbs are possible. It is also possible bradycardia, hypotension, impaired atrioventricular conduction, the appearance of symptoms of heart failure with peripheral edema, decrease in secretion of tear fluid, conjunctivitis, rhinitis, depression, disturbed sleep, nightmares, dry mouth, hypoglycemic state of diabetic patients, vomiting, diarrhea constipation Symptoms of bronchial obstruction may occur in susceptible patients. Separate cases of impaired liver function, thrombocytopenia, and allergic reactions – skin rash, itching.
Hypersensitivity, AV block II and III, sinoatrial block, acute or chronic (decompensated) heart failure, sick sinus syndrome, severe sinus bradycardia (HR less than 60 beats / min), cardiogenic shock, arterial hypotension (less than 100 BPH) mm Hg. Art.), expressed violations of the peripheral circulation, pregnancy, breast-feeding.
Hypotension is potentiated by sympatholytics, nifedipine, nitroglycerin, diuretics, hydralazine and other antihypertensive drugs. Antiarrhythmic and anesthetic agents increase the risk of developing bradycardia, arrhythmias, hypotension. Digitalis drugs potentiate the slowdown of AV conduction. Simultaneous i.v. administration of verapamil and diltiazem may cause cardiac arrest. Beta adrenomimetics, aminophylline, cocaine, estrogens, indomethacin and other NSAIDs weaken the antihypertensive effect. Strengthens and prolongs the action of anti-depolarizing muscle relaxants. The combination with alcohol leads to a mutual strengthening of the inhibitory effect on the central nervous system. Allergens increase the risk of severe systemic allergic reactions or anaphylaxis. Changes the effectiveness of insulin and oral antidiabetic agents and increases the risk of hypoglycemia. Antacids, oral contraceptives, cimetidine, ranitidine, phenothiazines – increase the level of metoprolol in the blood, rifampicin – reduces. Lowers the clearance of lidocaine, the effectiveness of beta2-adrenergic drugs (it is necessary to increase the dose of the latter). Incompatible with MAO inhibitors of type A.
Symptoms: arterial hypotension, acute heart failure, bradycardia, cardiac arrest, AV blockade, cardiogenic shock, bronchospasm, impaired breathing and consciousness / coma, nausea, vomiting, generalized convulsions, cyanosis (occur 20 minutes – 2 hours after administration). Treatment: gastric lavage, symptomatic therapy: administration of atropine sulfate (intravenously quickly 0.5–2 mg) – for bradycardia and AV conduction disturbance; glucagon (1-10 mg IV, then IV drip 2-2.5 mg / h) and dobutamine – in the case of a decrease in myocardial contractility; adrenomimetics (noradrenaline, adrenaline, etc.) – with arterial hypotension; diazepam (IV slow) – to eliminate seizures; inhalation of beta-adrenergic or in / in jet injection of aminophylline to relieve bronchospastic reactions; cardiac pacing.
Tablets of 50 and 100 mg in a package of 30; 100 and 200 pieces; 200 mg retard tablets per pack of 14; 1% solution in 5 ml ampoules in a package of 10 pieces.
List B. At a temperature not higher than + 25 ° С.
Betalok (Vetaloc) Bloksan (Vlocksan) Spesikor (Specikor), protein (Veloc) Lopresor (of Lopressor), Neoblok, Opresol (Orresol) Selopral (Selopral), Vazokardin, Korvitol, Metogeksal, MetololSmotrite a list of analogues of metoprolol drug.
With caution prescribed for diabetes mellitus (especially when labile), Raynaud’s disease and patients with impaired peripheral circulation, pheochromocetoma, pronounced impaired renal function and liver (in the appointment of Metoprolol-Acre in this category of patients, constant monitoring of the functional state of the liver and / or kidney). Patients using contact lenses should take into account that with the treatment with Metoprolol-Acre, a reduction in the production of tear fluid is possible. Termination of the course should take place gradually (for at least 10 days) under medical supervision. A few days before anesthesia with chloroform or ether, you must stop taking the drug. In the case of taking the drug before the operation, the patient should pick up a narcotic with minimal negative inotropic effects.
The instruction is compiled by a team of authors and editors of the site Piluli. The list of authors of the reference book of drugs is presented on the page of the editorial board of the site: Editing the site.