Included in the formulation
АТХ:C.01.B.C Antiarrhythmic drugs Ic class
Pharmacodynamics:The drug has an antiarrhythmic effect.
Refers to the IC subgroup of antiarrhythmic drugs. It mainly affects the sodium channels (both on the outer and inner surface of the cell membrane), reduces the amplitude and slows down the inactivation and reactivation of the fast sodium current. Blocks the input of calcium ions through slow channels. Lengthens the duration of refractory periods of the atria and AV node. Slows the rate of increase in the action potential in the atrial and ventricular fibers, Purkinje fibers and additional ways of carrying out. Increases the time of retrograde conduction through the AV node and the bundle of Kent. Inhibits sinoatrial conduction, especially in the syndrome of weakness of the sinus node, broadens the QRS complex on the ECG (by 25%), since it slows the conduction of the ventricles (in the Gis-Purkinje system). It has a negative inotropic effect, has local anesthetic and spasmolytic activity.
Pharmacokinetics:In conditions of intravenous administration, the half-distribution period is 4.5 minutes, the elimination half-life is 100 minutes, the volume of distribution is 144 liters, the total clearance is 0.8 liters per minute. When administered, the bioavailability is only about 20% (the effect of "first passage" through the liver), the half-absorption period is 46 minutes (food has no effect on absorption), the volume of distribution is 700 liters, binding to blood proteins is 90%, half-life - 134 min, the total ground clearance is 4 l / min. Biotransformiruetsya with the formation of active metabolites. It is excreted by the kidneys in the form of metabolites. Antiarrhythmic effect usually develops within 1-2 days. With the initial hypotension, intravenous administration can further lower blood pressure.
Indications:Supraventricular and ventricular extrasystole, paroxysms of fibrillation and atrial flutter; ventricular and supraventricular tachycardia, including those with Wolff-Parkinson-White syndrome.
IX.I30-I52.I45.6 Syndrome of premature agitation
IX.I30-I52.I47.1 Nadzheludochkovaya tachycardia
IX.I30-I52.I47.2 Ventricular tachycardia
IX.I30-I52.I48 Atrial fibrillation and flutter
IX.I30-I52.I49.4 Other and unspecified depolarization
Contraindications:Hypersensitivity expressed conduction disorders (including sinoatrial block, AV-block II and III degree in the absence of an artificial pacemaker, impaired intraventricular conduction) pronounced left ventricular hypertrophy, the presence of myocardial infarction, cardiogenic shock, severe hypotension, chronic heart failure II and III functional class, simultaneous administration of inhibitors monoamine oxidase, simultaneous use with other antiarrhythmic drugs IC (moracizin, propafenone, lappaconitin hydrobromide) and IA class (quinidine, procainamide, Disopyramide, aymalin), all forms of cardiac arrhythmias in combination with conduction block of His-Purkinje system, renal / hepatic failure, pregnancy, breast-feeding, age and 18 years of age (efficacy and safety have not been established).
Carefully:Possible reduction of side effects or their disappearance after application of the drug within 3-4 days. With prolonged treatment, they do not increase, and with the discontinuation of the drug quickly disappear.Side effects depend on the size of the dose and, to avoid them, do not prescribe the maximum dose of the drug.
As well as other antiarrhythmic drugs, the drug can act pro-arrhomogeneously, therefore, at its appointment, it is necessary to strictly take into account contraindications to use, to identify and eliminate hypokalemia in advance, to avoid using in combination with antiarrhythmic agents of IA and IC classes. It is preferable to begin course treatment in a hospital (especially in the first 3-5 days of taking the drug, taking into account the ECG dynamics after a trial and repeated doses of the drug or ECG monitoring data). Immediately stop treatment with increased ectopic ventricular complexes, the appearance of blockages or bradycardia, as well as with the expansion of ventricular complexes by more than 25%, a decrease in their amplitude, the duration of the P wave on the ECG is more than 0.12 s.
Pregnancy and lactation:Contraindicated in pregnancy.
The FDA action category is not defined.
For the duration of treatment, breastfeeding should be discontinued.
Dosing and Administration:Inside, intravenously.
Inside, the initial dose - 50 mg 2-3 times a day; with insufficient clinical effect, the dose is increased (under compulsory ECG monitoring) to 50 mg four times a day (200 mg) or 100 mg three times a day (300 mg).After achieving a clinical effect, it is possible to reduce the dose to a maintenance dose (the minimum effective dose and the duration of the course are selected individually).
Intravenously slow (only in hospital with ECG monitoring and arterial pressure): 0.3-0.6 mg / kg (preliminarily diluted in 10-20 ml isotonic sodium chloride solution), it is possible to re-enter after 6 hours.
Side effects:From the side of the cardiovascular system and blood (hematopoiesis, hemostasis): arrest of the sinus node, AV blockade, violation of intraventricular conduction, decreased myocardial contractility, decreased coronary blood flow, arrhythmia (pro-arrhythmic effect is most likely after a heart attack and other cardiac pathologies leading to a decrease in muscle contractility and heart failure), changes on the ECG (prolongation of the PQ interval, extension of the P wave and the QRS complex).
From the nervous system and sensory organs: dizziness, headache, staggering when walking or turning the head, drowsiness, diplopia, a violation of accommodation.
Other: nausea.
Overdose:Symptoms: prolongation of the PR interval and expansion of the QRS complex, increased amplitude of the T wave, bradycardia, sinoatrial and AV blockade, asystole, paroxysms of polymorphic and monomorphic ventricular tachycardia, decreased myocardial contractility, persistent blood pressure lowering, dizziness, blurred vision, headache, gastrointestinal disorder.
Treatment: symptomatic therapy; for the treatment of ventricular tachycardia, antiarrhythmic agents of IA and IC classes should not be used;
sodium hydrogen carbonate can eliminate the expansion of the QRS complex, bradycardia and arterial hypotension.
Interaction:Incompatible with other antiarrhythmic drugs of quinidine and inhibitors monoamine oxidase (increased risk of arrhythmia).
Special instructions:The following are considered risk factors for the pro-rhythmogenic effect of the drug: organic heart disease (especially - myocardial infarction suffered), lowering of left ventricular ejection fraction, maximum dose of the drug. In addition, caution should be exercised in patients with liver disease. Do not use alcohol while taking drugs.
During therapy it is necessary to regularly monitor the patient's condition and function of the cardiovascular system (ECG, arterial pressure, echocardiogram).
During treatment, it is not recommended to drive vehicles or handle complex mechanisms, since these activities require increased attention and capacity for concentration.