The absorption of metoprolol by oral administration is almost complete and does not depend on food intake, however, bioavailability is about 50% due to the intensive metabolism during the first passage through the liver. metoprolol no prescription With prolonged use, bioavailability increases due to a decrease in blood circulation in the liver and saturation of liver enzymes.
After oral administration, the maximum concentration of the drug in plasma is observed after 1-2 hours. In plasma, Metoprolol binds to proteins by 5-25%. The elimination half-life makes 3-7 hours. At the first passage through the liver, about 65-80% of the drug is metabolized. Excreted by the kidneys in the form of metabolites. Metoprolol is a lipophilic β-blocker. About 90% is absorbed in the digestive tract, penetrates well through the blood-brain barrier.
A cardioselective β-blocker, without its own sympathomimetic and membrane-stabilizing activity, acts mainly on β1-receptors of the heart, to a lesser extent on β2-receptors of peripheral vessels and bronchi. It has antihypertensive, antianginal and antiarrhythmic effects. The drug is characterized by a negative inotropic effect, reduces myocardial contraction, cardiac output, sinus node automatism, heart rate, slows atrioventricular conduction. Suppresses the stimulating effect of catecholamines on the heart during physical and psycho-emotional stress. In patients with coronary heart disease has an anti-ischemic and antianginal effect. With angina pectoris, metoprolol reduces the number and severity of attacks, increases tolerance to physical activity; contributes to the normalization of heart rhythm. With myocardial infarction, it helps to limit the zone of necrosis of the heart muscle; reduces the risk of fatal arrhythmias and recurrences of myocardial infarction. It has an antihypertensive effect, which stabilizes by the end of the 2nd week of regular use. Unlike non-selective β-blockers, Metoprolol, when used in medium therapeutic doses, has a less pronounced effect on the smooth muscles of the bronchi and peripheral arteries, insulin release, carbohydrate and lipid metabolism.
Pregnancy and lactation
Breastfeeding is a list of absolute contraindications. Pregnant women should take the drug with caution, since the components of the tablets penetrate the placental barrier and can harm the baby. A doctor may prescribe Metoprolol treatment to a pregnant woman if the risk to her life and health exceeds the possible negative consequences for the child.
The drug can cause developmental delay, bradycardia, hypertension, hypoglycemia. If a woman took the drug during the gestation period, she should inform the doctor about it. Doctors take the baby immediately after birth for several days to monitor its condition and the presence of congenital abnormalities.
I have long known that I have a problem with the cardiovascular system and I try to do everything so as not to put a strain on the heart. But when pressure rises, it’s simply not possible to endure. He came to the reception and the doctor advised Metoprolol. I started taking it and it got a lot easier.
Cardioselective beta1-blocker without internal sympathomimetic activity. http://medlineplus.gov/druginfo/meds/a682864.html It has a slight membrane stabilizing effect. It has antihypertensive, antianginal and antiarrhythmic effects. It suppresses the stimulating effect of catecholamines on the heart during physical and psycho-emotional stress: it prevents the increase in heart rate, blood pressure increase, reduces cardiac output and reduces myocardial contractility.
Due to the peculiarities of the dosage form, a constant concentration of metoprolol in plasma is maintained and a stable clinical effect of the drug is ensured for 24 hours. Due to the absence of peak concentration in plasma, Betalok® ZOK clinically has better beta1 selectivity compared to the traditionally used tablet forms of metoprolol. In addition, the potential risk of side effects observed at peak plasma concentrations of the drug (e.g., bradycardia or weakness in the legs when walking) is significantly reduced..
When used in medium therapeutic doses, Betaloc® ZOK has a less pronounced effect on the smooth muscles of the bronchi than non-selective beta-blockers. If necessary, Betalok® ZOK in combination with beta2-adrenergic agonists can be prescribed to patients with obstructive pulmonary disease.
Betalok® ZOK has a lesser effect on insulin secretion and carbohydrate metabolism and on the activity of the cardiovascular system under hypoglycemia compared with non-selective beta-blockers.
The use of Betaloc® ZOK for arterial hypertension leads to a significant decrease in blood pressure for more than 24 hours (in the supine position, standing, under load). At the beginning of metoprolol therapy, an increase in OPSS is noted. With prolonged use, a decrease in blood pressure is possible due to a decrease in OPSS with a constant cardiac output.
In the MERIT-HF, a study of survival in chronic heart failure (NYHA Class II-IV functional class) with a reduced ejection fraction (? 40%), which included 3991 patients, Betalok® ZOK showed an increase in survival and a decrease in hospitalization frequency. With prolonged treatment, patients achieved a general improvement in well-being, a weakening of the severity of symptoms (according to the NYHA functional classes). Also, therapy with Betaloc® ZOK showed an increase in the ejection fraction of the left ventricle, a decrease in the final systolic and final diastolic volumes of the left ventricle.
The quality of life during the treatment with Betalok® ZOK does not deteriorate or improve. Improving the quality of life during treatment with Betaloc® ZOK was observed in patients after myocardial infarction.