Drug Title

Toprol XL (Metoprolol)

Pharmacological action

Cardioselective beta1-adrenoblocker without intrinsic sympathomimetic activity. It has hypotensive, antianginal and antiarrhythmic effects. It reduces automatism of sinus node, decreases heart rate, slows down AV conduction, reduces myocardial contractility and excitability, decreases cardiac output, reduces myocardial oxygen demand. Suppresses the stimulating effect of catecholamines on the heart during physical and psycho-emotional stress.

Causes a hypotensive effect that stabilizes by the end of the 2nd week of treatment. In tension angina metoprolol reduces the frequency and severity of attacks. Normalizes heart rhythm in supraventricular tachycardia and atrial fibrillation. In myocardial infarction contributes to limiting the zone of ischemia of the heart muscle and reduces the risk of fatal arrhythmias, reduces the possibility of recurrence of myocardial infarction. Prevents the development of migraine.

When used in medium therapeutic doses, unlike non-selective beta-adrenoblockers, it has less pronounced effect on the organs containing β2-adrenoreceptors (pancreas, skeletal muscles, smooth muscle of peripheral arteries, bronchi and uterus) and on carbohydrate metabolism. During long-term use, it reduces the concentration of cholesterol in the blood. When used in high doses (more than 100 mg/day) it has a blocking effect on both β-adrenoreceptor subtypes.

Pharmacokinetics

Toprol XL (Metoprolol) is rapidly and almost completely absorbed from gastrointestinal tract after oral administration, Cmax of active substance in blood plasma is reached after 1-2 hours. After absorption, metoprololol is largely subjected to the effect of "first passage" through the liver. Binding to plasma proteins is low, about 5-10%. Vd is 5.6 l/kg. It is rapidly distributed in the tissues, penetrates through the BBB and the placental barrier. It is excreted with breast milk. Metoprolol undergoes oxidative metabolism in liver (mainly with the participation of CYP2D6 isoenzyme) to form 3 main metabolites, none of which has clinically significant beta-adrenoblocking effect. T1/2 of metoprolol from plasma is 3-4 h and does not change during treatment. More than 95% of the administered dose is excreted by the kidneys, about 5% of the administered dose is excreted unchanged by the kidneys.

Contraindications to use

Hypersensitivity to metoprolol or other beta-adrenoblockers; Grade II or III AV-blockade (without pacemaker); decompensated heart failure; patients receiving long-term or intermittent therapy with inotropic agents and agents acting on β-adrenoreceptors; clinically significant sinus bradycardia; CCIA; cardiogenic shock; severe peripheral circulatory disorders, including those with threat of gangrene; arterial hypotension (systolic BP less than 100 mm Hg). including at risk of gangrene; arterial hypotension (systolic BP less than 100 mm Hg. Hg); patients with acute myocardial infarction (heart rate less than 45 beats/min, PQ interval duration greater than 0.24 sec or systolic BP less than 100 mm Hg); for treatment of supraventricular tachycardia with systolic BP less than 110 mm Hg. ; intravenous administration of calcium channel blockers like verapamil and diltiazem; simultaneous use of MAO inhibitors; severe forms of bronchial asthma and COPD; pheochromocytoma (without simultaneous use of alpha-adrenoblockers); breast-feeding period; children under 18 years old.

Caution

Class I AV blockade; Prinzmetal's angina pectoris; COPD and mild bronchial asthma; diabetes mellitus; severe renal insufficiency.

Administration during pregnancy and lactation

Use during pregnancy is possible only when the anticipated benefit to the mother exceeds the potential risk to the fetus. Metoprolol penetrates through the placental barrier. Due to the possible development of bradycardia, arterial hypotension, hypoglycemia and respiratory arrest in the newborn, metoprololol should be withdrawn 48-72 h before the planned delivery date. After delivery, the newborn's condition should be closely monitored for 48-72 h.

It is excreted with breast milk. Administration during breast feeding is contraindicated.

Administration in patients with liver dysfunction

Caution is advised when using in patients with severe hepatic impairment.

Administration in patients with impaired renal function

Caution is advised when using in patients with severe renal insufficiency.

Administration in children

It is contraindicated in children and teenagers under 18 years old.

Administration in elderly patients

It is recommended to start the treatment at a dose of 50 mg/day in elderly patients, since a sharp BP decrease or increasing bradycardia may be more pronounced.

Indications of Metoprolol active substances

Arterial hypertension, prophylaxis of angina attacks, cardiac pacing disorders (supraventricular tachycardia, extrasystole), secondary prophylaxis after myocardial infarction, hyperkinetic cardiac syndrome (including in hyperthyroidism, NCD). Prevention of migraine attacks.

Dosing regimen

The optimal dosing regimen is determined by the doctor. It should be strictly adhered to in accordance with the dosage form used for the particular drug indications and the dosing regimen.

When administered orally, the average dose is 100 mg / day in 1-2 doses. If necessary, the daily dose is gradually increased to 200 mg. When intravenously administered, a single dose is 2-5 mg; if there is no effect, reintroduction is possible after 5 minutes.

Maximal doses: when administered orally, daily dose is 400 mg; when administered intravenously, a single dose is 15-20 mg.