Metoprolol, tablets 50 mg 30 pcs

Metoprolol belongs to the cardioselective β-adrenoreceptor blockers with no intrinsic sympathomimetic activity and membrane stabilizing properties. It has hypotensive, antianginal and antiarrhythmic effects.

Blocking in low doses the β-adrenoreceptors of heart, it decreases catecholamine-stimulated formation of cAMP from ATP, decreases intracellular Ca2+ flow, produces negative chrono-, dromo-, batmo- and inotropic action (decreases heart rate, inhibits conduction and excitability and decreases myocardial contractility).

The total peripheral resistance at the beginning of β-adrenoblocker administration (in the first 24 h after oral administration) – increases (as a result of reciprocal increase of α-adrenoreceptor activity and elimination of β-adrenoreceptor stimulation), which returns to baseline after 1-3 days, and decreases with long-term administration.

. Acute antihypertensive effect is due to a decrease in cardiac output, a stable antihypertensive effect develops over 2-3 weeks and is due to a decrease in renin synthesis, and plasma renin accumulation, Inhibition of renin-angiotensin system activity (of great importance in patients with initial renin hypersecretion) and CNS restoration of aortic arch baroreceptors sensitivity (there is no increase of their activity in response to blood pressure decrease) and, finally, reduction of peripheral sympathetic effects. Reduces elevated BP at rest, under physical stress and strain.

The antianginal effect is determined by reducing myocardial oxygen demand as a result of decreased heart rate (prolongation of diastole and improvement of myocardial perfusion) and contractility, as well as decreased myocardial sensitivity to the effects of sympathetic innervation. It reduces the number and severity of angina attacks and increases exercise tolerance. Blood pressure decreases in 15 minutes, maximum in 2 hours and lasts for 6 hours; diastolic BP changes slower: stable decrease is observed after several weeks of regular use.

The antiarrhythmic effect is caused by the elimination of arrhythmogenic factors (tachycardia, increased activity of the sympathetic nervous system, increased content of CAMF, arterial hypertension), the decrease of spontaneous excitation rate of sinus and ectopic pacemakers and AV conduction slowing down (mainly in antegrade and, to smaller extent, in retrograde direction via AV node) and via additional pathways. In supraventricular tachycardia, atrial fibrillation, sinus tachycardia in functional heart disease and hyperthyroidism, it reduces the heart rate, or may even lead to restoration of sinus rhythm. Prevents the development of migraine.

In medium therapeutic doses, unlike non-selective beta-adrenoblockers, it has less effect on the organs containing β-adrenoreceptors (pancreas, skeletal muscles, smooth muscles of peripheral arteries, bronchi and uterus) and on carbohydrate metabolism. When used in high doses (more than 100 mg/day) it has a blocking effect on both β-adrenoreceptor subtypes.

Indications

– arterial hypertension (as monotherapy or in combination with other antihypertensive agents), including hyperkinetic type, tachycardia;

– coronary heart disease: myocardial infarction (secondary prevention-complex therapy), prevention of angina attacks;

– Heart rhythm disorders (supraventricular tachycardia, ventricular extrasystole);

– hyperthyroidism (complex therapy);

– prevention of migraine attacks.

Active ingredient

Composition

Metoprolol tartrate 50 mg.

Auxiliary substances:

colloidal anhydrous silicon dioxide,

microcrystalline cellulose,

sodium carboxymethyl starch (type A),

magnesium stearate.

Shell composition:

hypromellose, polysorbate 80, talc, titanium dioxide (E171), crimson dye (Ponceau 4R).

How to take, the dosage

The tablets are taken orally with a small amount of liquid, without chewing, with food or immediately after a meal.

The tablets can be divided.

The course of treatment is not limited in time and depends on the course of the disease.

If necessary to stop treatment, the dose is reduced gradually (at least for 10 days) under a physician’s supervision.

Arterial hypertension:

The initial daily dose is 50-100 mg in 1-2 doses (morning and evening).

In case of insufficient therapeutic effect, the daily dose may be gradually increased to 100-200 mg.

The maximum daily dose is 200 mg.

Stenocardia, arrhythmias, prevention of migraine attacks

100-200 mg daily in two doses (morning and evening).

Secondary prevention of myocardial infarction

200 mg per day in two doses (morning and evening).

Functional cardiac disorders accompanied by tachycardia

100 mg per day in two doses (morning and evening).

When therapeutic effect is achieved, the dose is reduced (under medical supervision).

Elderly patients are recommended to start treatment with 50 mg/day.

Interaction

In concomitant use of metoprolol and verapamil, cardiac output, stroke volume and pulse rate decrease. If verapamil is administered intravenously during metoprolol administration, there is a risk of cardiac arrest.

Concomitant use of metoprolol with calcium channel blockers, cardiac glycosides, reserpine, nitrates, clonidine increases the risk of arterial hypotension, bradycardia, AV block. Metoprolol increases the effect of hypoglycemic drugs. Indomethacin and other NSAIDs, as well as estrogens reduce the hypotensive effect of metoprolol.

The administration of agents for inhalation anesthesia against the background of metoprolol use increases the risk of myocardial function depression and development of arterial hypotension.

Rifampicin decreases the blood concentration of metoprolol. Plasma levels of metoprololol are increased with concomitant administration of hydralazine, oral contraceptives, ranitidine, cimetidine.

Contraindications

AV blockade of II, III degree, sinoatrial block, bradycardia (heart rate less than 50 beats/min), CCSU, arterial hypotension, chronic heart failure II B-III stages, acute heart failure, cardiogenic shock, metabolic acidosis, marked peripheral circulatory disorders, hypersensitivity to metoprolol.

Side effects

Cardiovascular system disorders: bradycardia, arterial hypotension, AV conduction disorders, occurrence of symptoms of heart failure are possible.

Digestive system disorders: at the beginning of therapy dry mouth, nausea, vomiting, diarrhea, constipation; liver function disorders in single cases.

CNS and peripheral nervous system disorders: weakness, fatigue, dizziness, headache, muscle cramps, cold sensation and paresthesia in extremities may occur; decreased tear fluid secretion, conjunctivitis, rhinitis, depression, sleep disorders, nightmares may occur.

Hematopoietic system: in some cases – thrombocytopenia.

Endocrine system disorders: hypoglycemic states in patients with diabetes.

Respiratory system: in predisposed patients there may be symptoms of bronchial obstruction.
Allergic reactions: skin rash and itching.

Overdose

Symptoms: severe sinus bradycardia, dizziness, nausea, vomiting, cyanosis, marked BP decrease, arrhythmia, ventricular extrasystole, bronchospasm, syncope, in acute overdose – cardiogenic shock, loss of consciousness, coma, atrioventricular block (up to complete transverse block and cardiac arrest), cardialgia. The first signs of overdose occur 20 minutes to 2 hours after taking the drug.

Treatment: gastric lavage and administration of adsorptive agents; symptomatic therapy: in case of marked BP decrease the patient should be in Trendelenburg position; in case of excessive BP decrease, bradycardia and heart failure – intravenous, with 2-5 min intervals, ba-adrenostimulants – until the desired effect is achieved or intravenous 0.5-2 mg of atropine sulfate. If there is no positive effect, dopamine, dobutamine or norepinephrine (noradrenaline). As a follow-up, it is possible to prescribe 1-10 mg of glucagon, setting of transvenous intracardiac pacing. For bronchospasm, IV beta 1 -adrenoreceptor stimulants should be administered. In case of seizures, slow intravenous administration of diazepam. Hemodialysis is not effective.

Similarities