Allapinin tablets belong to the first class of the group of antiarrhythmic drugs. The drug is able to block sodium channels in the membranes of cardiomyocytes. It provokes a slowdown in intraventricular and atrioventricular conduction, shortens the functional and effective refractory periods in the atria, His bundle, AV node and Purkinje fibers. The tool has absolutely no effect on the duration of the QT interval, the frequency of contractions.
In the initial absence of manifestations of insufficiency of cardiac function, the drug Allapinin (instructions for use contains such information) does not affect myocardial contractility. Does not affect the conductivity of the atrioventricular node in the anterograde direction. The tool does not have a negative hypotensive effect. In practice, its inotropic effect is not noted. When taking the medicine, automatism in the sinus node is not depressed. It has antispasmodic, local anesthetic, as well as anticholinergic action in a moderate, not having clinical significance, degree. It has insignificant coronary expansion, sedative properties. The effect with oral administration is observed after forty or sixty minutes. The maximum activity reaches after 80 minutes. The duration of the therapeutic effect is from 8 hours.
Pharmacokinetics in General
Bioavailability is about 40%. The drug is metabolized in the liver and is able to penetrate the BBB. Withdrawal of the drug occurs in the urine. In case of impaired renal activity, the excretion period increases by 2-3 times.
What are the indications for use of Allapinin?
The medicine is prescribed for ventricular and supraventricular extrasystoles and tachycardia of a paroxysmal type (without lesions in the heart of an organic nature and with WPW syndrome), atrial flutter and paroxysms.
Dosage regimen
The drug “Allapinin” recommends the use of the drug in a dosage of 25 mg once every 8 hours. In the absence of a pronounced therapeutic result, the medication is taken every 6 hours. In some cases, a single dose is doubled (up to 50 mg). The time interval is 6-8 hours.
A maximum of 300 mg is allowed per day. The duration of therapy and the appropriateness of adjusting the intake regimen is established by a specialist. The medicine is drunk after a meal. Grind or break this product is not allowed.
Allapinin medication: side effects
Subject to the prescriptions of the doctor, the drug is tolerated by patients of different ages quite well. However, there is a likelihood of the development of undesirable consequences on the basis of therapy with Allapinin. Side effects may have a different degree of severity. The tool can provoke disorders in the activity of the peripheral and central nervous systems.
In particular, dizziness, diplopia, ataxia appear. Among the negative consequences of the effect of the drug on the cardiovascular system, experts note probable disturbances in intraventricular and atrioventricular conduction, the development of sinus tachycardia (with prolonged use). Undesirable manifestations include arrhythmogenic effect, lengthening of the QP interval, expansion of the QRS complex, and other changes in the ECG picture. On the basis of therapy with the Allapinin medicine (instructions for use warns about this), there is hyperemia of the skin, pain in the head, or a feeling of heaviness. Some patients experience an allergic reaction (rash or skin irritation). Contains information on the undesirable effects of the drug "Allapinin" instructions for use. Reviews of experts on the tolerance of the drug, in general, are positive. However, given the seriousness of some of the negative consequences, the drug is administered under close medical supervision.
If complications occur and worsen, you should immediately visit a specialist. In this case, the doctor may choose similar drugs instead of Allapinin.
When is a medication not prescribed?
Contraindications include cardiogenic shock, atrioventricular block in the third and second degree (in the absence of an artificial heart rate driver). It is not allowed to drink the medicine for arterial hypertension in a difficult period (with systolic pressure less than 90 mm / Hg), hypertrophy in the left ventricular myocardium of a pronounced nature. Prohibited medication for post-infarction cardiosclerosis. The drug is not recommended for blockade in the right leg of the bundle of His (when combined with violations in the branches on the left side), chronic heart failure of moderate and severe course. The medicine is contraindicated until 18 years of age (due to the fact that the safety and effectiveness of the drug have not been established), fructose intolerance. It is not allowed to take medication for people with a syndrome of impaired absorption of galactose / glucose, pregnancy, with isomaltase / sucrose deficiency. The drug is not recommended for hypersensitivity to the components. If therapy is necessary for a nursing patient, lactation must be stopped.
When is a dose adjustment required?
Sometimes there is a need to change the regimen of the Allapinin medication. Instructions, reviews of specialists contain information that reducing the amount of the drug or increasing the interval between doses can be recommended for atrioventricular blockade in the first degree, disorders in intraventricular conduction, bradycardia. Caution is observed with angle-closure glaucoma, circulatory disorders (peripheral) of a severe nature, hypertrophy in the tissues of the prostate. Correction of the circuit is needed on the basis of changes in electrolyte metabolism, conductivity in Purkinje fibers, blockade in one of the legs in the bundle of His. Caution is also necessary when taking other anti-rhythmic drugs simultaneously with the Allapinin medicine. Reviews of many experts are very categorical on the issue of changing the dosage in the absence of effect.
additional information
Before starting therapy, the disorders in the water-electrolyte balance are eliminated, in the process of taking the medication, it is necessary to ensure constant and careful control over it. The threshold for cardiac stimulation may increase in people who have had a heart attack (acute), with heart failure, or who have an artificial pacemaker. In case of dizziness, diplopia, headaches, it is recommended to reduce the dosage. When sinus tachycardia appears on the basis of prolonged administration of the drug, beta-blockers are prescribed if necessary. These drugs are recommended in low doses. Because of therapy, caution must be exercised when engaging in potentially hazardous activities, when increased attention and rapid concentration or reaction are required.
Overdose
Due to the fact that the drug has a small breadth of therapeutic activity, severe intoxication can develop quite easily. Especially the risk of poisoning is high when taking other antiarrhythmic drugs. With an overdose, there is an elongation of the PR and QT intervals, an increase in the amplitude of the T-wave, and an expansion of the QRS complex. Against the background of intoxication, asystole, bradycardia occurs, contractility in the myocardium decreases. The patient also has sinotrial blockade, a decrease in pressure of a pronounced nature, an indigestion. Intoxication is accompanied by paroxysms of ventricular polymorphic tachycardia, blurred vision, dizziness, pain in the head. If an overdose occurs, symptomatic therapy is indicated. Ventricular tachycardia is treated with antiarrhythmic drugs of categories I A and I C. The expansion of the QRS complex, arterial hypotension and bradycardia are eliminated with sodium bicarbonate.
Interaction with other medicines
When taken simultaneously with inducers of microsomal hepatic enzymes, the effectiveness of the drug Allapinin is reduced. This increases the risk of toxic effects. When taking antiarrhythmic drugs of other classes, the likelihood of developing arrhythmogenic effects increases. The tool also enhances the activity of non-depolarizing muscle relaxants.
What is an effective drug with a similar mechanism of action?
The Allaritmin product contains the same active substance as the Allapinin medicine, lappaconitine hydrobromide. The medication belongs to class I antiarrhythmic drugs. The medicine “Alaritmin” is available in tablet form and as a solution for injection into a muscle or vein. With oral administration, the effect of the medication occurs in about an hour. After 4-5 hours, efficiency reaches its maximum. Duration of action - 8 or more hours. When injected into a vein, the effect of the drug comes faster - after 15-20 minutes. Unlike the Allapinin medication, the Allaritmin drug is recommended to drink 3 times a day, 25 mg each. Take the medicine before meals. Tablets are preferably crushed. In the absence of effectiveness, an increase in dosage and frequency of administration is allowed. Intravenous administration is carried out slowly, over 5 minutes. The dosage is set in accordance with the weight of the patient. Recommended at 0.3-0.4 mg / kg. In some cases (especially severe), the drug is administered again after 6 hours. 0.4 mg / kg is prescribed in the muscle with an interval of 6 hours. It should be noted that intravenous administration is not recommended at home. The drug "Alaritmin" has the same restrictions on the use of the drug "Allapinin." Treatment is carried out in a hospital with constant medical supervision and ECG monitoring. This is especially important in the treatment of patients with the first degree of atrioventricular block, chronic heart failure of a decompensated type.
Conclusion
Allapinin, the use of which should be strictly controlled, like other antiarrhythmic drugs, belongs to the category of potent medicines. In the absence of a therapeutic effect when taking the dosage prescribed by a specialist, you should not increase it yourself. This is due to the fact that there is a risk of intoxication with subsequent complications. Before prescribing a medication, the doctor should inform the patient about the likely side effects and contraindications. In turn, the patient talks about the presence of intolerance, including in the anamnesis, to any means, as well as about the drugs that he takes additionally. Before taking the medicine, you should study the annotation.