Metoprolol
The simultaneous use of METOPROLOL with the following drugs should be avoided:
Verapamil
The combination of beta-blockers (atenolol, propranolol and pindolol) and verapamil can cause bradycardia and lead to a decrease in blood pressure. Verapamil and beta-blockers have complementary inhibitory effects on AV conduction and sinus node function. Intravenous administration of verapamil is contraindicated in patients receiving beta-blockers.
Diltiazem
Diltiazem and beta-blockers mutually enhance the inhibitory effect on AV conduction and sinus node function. Cases of severe bradycardia have been reported with the combination of metoprolol and diltiazem. Intravenous administration of diltiazem is contraindicated in patients receiving beta-blockers.
Propaphenone
When using propafenone, four patients treated with metoprolol experienced an increase in plasma concentrations of metoprolol by 2-5 times, while two patients experienced side effects characteristic of metoprolol. This interaction was confirmed in a study on 8 volunteers. The interaction is likely due to propafenone's inhibition, like quinidine, of the metabolism of metoprolol via the CYP2D6 isoenzyme. Taking into account the fact that propafenone has beta-blocker properties, the simultaneous use of metoprolol and propafenone does not seem advisable.
Monoamine oxidase inhibitors (MAO)
Concomitant use with MAO inhibitors is not recommended due to a significant increase in antihypertensive effect. The treatment break between taking MAO inhibitors and metoprolol should be at least 14 days.
Patients concomitantly taking metoprolol and other beta-blockers (eye drops), symptomatic agents, ganglion blockers or MAO inhibitors should be closely monitored.
Barbituric acid derivatives
Barbiturates (study conducted with pentobarbital) increase the metabolism of metoprolol due to the induction of microsomal liver enzymes.
The combination of METOPROLOL with the following drugs may require dose adjustment:
Class I antiarrhythmic drugs
Class I antiarrhythmics and beta blockers may result in additive negative inotropic effects, which can cause serious hemodynamic side effects in patients with impaired left ventricular function. This combination should also be avoided in patients with sick sinus syndrome and impaired AV conduction.
Quinidine
Quinidine inhibits the metabolism of metoprolol in a special group of patients with rapid hydroxylation (in Sweden, approximately 90% of the population), causing mainly a significant increase in plasma concentrations of metoprolol and increased beta-adrenergic receptor blockade. It is believed that a similar interaction is typical for other beta-blockers, in the metabolism of which the CYP2D6 isoenzyme takes part.
Amiodarone
Concomitant use of amiodarone and metoprolol increases the risk of developing severe sinus bradycardia. Given the long half-life of amiodarone (50 days), a possible interaction should be considered long after discontinuation of amiodarone.
Epinephrine (adrenaline)
Ten cases of severe hypertension and bradycardia have been reported in patients taking concomitant non-selective beta blockers (including propranolol and pindolol) and epinephrine. The interaction was also observed in the group of healthy volunteers.
It is assumed that similar reactions can be observed when epinephrine is used simultaneously with local anesthetics if they accidentally enter the vascular bed. This risk is expected to be much lower with cardioselective beta blockers.
Phenylpropanolamine (norephedrine)
Phenylpropanolamine in a single dose of 50 mg can cause an increase in diastolic blood pressure to pathological values in healthy volunteers. Propranolol mainly prevents the increase in blood pressure caused by phenylpropanolamine. However, beta-blockers may cause the development of paradoxical arterial hypertension in patients receiving phenylpropanolamine. Several cases of hypertensive crisis have been reported while taking phenylpropanolamine.
Antihypertensive drugs
When taken simultaneously with antihypertensive drugs, diuretics, angiotensin-converting enzyme inhibitors, nitroglycerin or blockers of “slow” calcium channels, a sharp decrease in blood pressure may occur. Particular caution is required when combining metoprolol with prazosin.
Clonidine
Hypertensive reactions during abrupt withdrawal of clonidine may be exacerbated by concomitant use with beta-blockers. If metoprolol and clonidine are taken simultaneously, then when metoprolol is discontinued, clonidine is discontinued after a few days (due to the risk of withdrawal syndrome).
Cardiac glycosides
Cardiac glycosides, when used together with beta-blockers, can increase atrioventricular conduction time and cause bradycardia.
Nonsteroidal anti-inflammatory drugs (NSAIDs)
NSAIDs weaken the antihypertensive effect of beta-blockers. This interaction has been documented for indomethacin. It is likely that the described interaction will not be observed with sulindac. No interaction was noted in studies with diclofenac.
CYP2D6 inhibitors
Metoprolol is a substrate of the CYP2D6 isoenzyme, and therefore, drugs that inhibit the CYP2D6 isoenzyme (quinidine, terbinafine, paroxetine, fluoxetine, sertraline, celecoxib, propafenone and diphenhydramine) may affect the concentration of metoprolol in the blood plasma. The concentration of metoprolol in the blood plasma may increase when combined with cimetidine, hydralazine, selective serotonin reuptake inhibitors (such as paroxetine, fluoxetine and sertraline). Diphenhydramine reduces the clearance of metoprolol to alpha-hydroxymetoprolol by 2.5 times. At the same time, an increase in the effect of metoprolol is observed.
Rifampicin
Rifampicin may increase the metabolism of metoprolol, reducing its plasma concentration.
Other drug interactions
During the use of metoprolol, dose adjustment of oral hypoglycemic agents may be required.
Allergens used for immunotherapy or allergen extracts for skin testing increase the risk of severe systemic allergic reactions or anaphylaxis in patients receiving metoprolol.
Iodine-containing radiocontrast agents for intravenous administration increase the risk of anaphylactic reactions.
Metoprolol reduces the clearance of xanthines (except diphylline), especially in patients with initially increased clearance of theophylline under the influence of smoking. Reduces the clearance of lidocaine, increases its concentration in the blood plasma.
Metoprolol enhances and prolongs the effect of antidepolarizing muscle relaxants and prolongs the anticoagulant effect of coumarins.
When metoprolol is used together with anxiolytics and drugs with hypnotic activity, the antihypertensive effect is enhanced.
When metoprolol is used together with ethanol, the risk of a pronounced decrease in blood pressure increases and the inhibitory effect on the central nervous system increases.
There is an increased risk of peripheral circulatory disorders when metoprolol is used together with ergot alkaloids.
With the use of beta-blockers, inhalational anesthetics enhance the cardiodepressive effect.
METOPROLOL (tablets)
I didn’t get hung up on it (it’s not in my nature to go to doctors), and it didn’t particularly bother me.
True, there were interruptions in the rhythm, a regular cardiogram showed tachycardia. And then by chance, after the operation in 2013, they decided to put me on a HOLTER device; they installed it several times for confirmation, plus an additional examination of the heart’s functioning. The diagnosis was disappointing - arrhythmia, but it turns out this is far from tachycardia. That’s when I was prescribed the drug “Metaprolol-ratiopharm”; I have been taking it for three years now.
The drug "Metaprolol-ratiopharm" (photo):
The drug "Metaprolol-ratiopharm" is in a regular cardboard box; the package contains three blisters of ten tablets each, for a total of thirty pieces per package.
The drug “Metaprolol-ratiopharm” is a selective adrenergic blocker; we will learn what it is further from the instructions, which are necessarily attached to the drug.
From the description below you can understand that the medicine is made in Germany and the tablets have a dose of 50 ml (photo):
The active substance of the drug and auxiliary substances are also indicated; the medicine can be bought without a prescription; its storage conditions (photo):
The date of manufacture of the medicine and its expiration date must be indicated (photo):
Type of medicine blister (photo):
And this is what the “Metaprolol-ratiopharm” tablets, 50 ml, look like.
The instructions attached to the medicine are very voluminous and detailed, since this is not an easy medicine, but for regulating heart rate (photo):
As usual, at the very beginning of the instructions for the medicinal product, a detailed description of this drug is given and what 1 tablet contains (its composition) (photo):
The pharmacological group is indicated.
The pharmacological actions of the drug are described in detail, what it does and what it has (photo):
Indications for use are listed, mainly for various cardiac disorders, but what is interesting is that this drug is also used for migraines (photo):
There are contraindications and there are quite a lot of them (photo):
Special instructions for careful use (photo):
Method of use of the drug and dose (photo):
But of course, it is strictly individual and must be selected according to how you feel.
There are side effects (photo):
There are a number of other instructions.
I will give only special instructions (photo):
It may show that this is a very serious remedy and difficult to use, but this is far from the case, I can assure you.
I won’t go into details about what kind of arrhythmia I have, but I’ll just say that it’s an irregular rhythm and, on top of that, shortness of breath if you go up the stairs, no matter what floor. Therefore, you can walk on a flat surface for as long as you like, but as soon as you start to climb to the top, it’s already a disaster. Anyone who has encountered or is experiencing something similar will understand me.
The initial dose that the cardiologist prescribed to me was 0.25 ml, that is, 1/4 of a 50 ml tablet, which should be taken three times a day at any time, regardless of meals. The dose turned out to be small, but he added that it is necessary to take this medicine for the rest of your life, since it does not cure, but only maintains the heart rate normal.
As the doctor prescribed, I took this medicine for about six months, but all this time I felt some discomfort. True, I note that climbing the stairs became more comfortable, there was no shortness of breath. Since I am naturally hypotensive and my blood pressure is always low, and this medicine turns out to lower my blood pressure, it became even lower, I began to feel dizzy often, and it turns out that my blood pressure has dropped. I had to change the dosage. As the cardiologist said, you can select the dose yourself based on how you feel.
I have currently found the optimal dosage for myself: 1/2 tablet 50 ml and take it in the morning once a day (enough for me for a day) and so on every morning. If I don’t leave the house, I try not to take the medicine (this is 1-2 times a week), but if I don’t take it more often, arrhythmia attacks occur mainly at night during sleep, I can’t explain this.
I tried to save money, although the product is cheap and costs literally pennies, I bought a dosage of 100 ml, but this dosage turned out to be very inconvenient for me personally to use, I refused.
I hope that my experience in using this medicine will help some of you. The product is very effective, I recommend it! I know that there is an expensive analogue that is now often prescribed, but I don’t think it’s worth doing it! Thank you for your attention!
