Description of the active substance:
This information is a reference and it is not enough that the drug has been prescribed by a doctor ..
PHARMACHOLOGIC EFFECT
Selective calcium channel blocker II class, a derivative of dihydropyridine. It inhibits the flow of calcium into cardiomyocytes and smooth muscle cells of blood vessels. Has antianginal and hypotensive effect. Reduces the tone of the smooth muscles of blood vessels. Expands coronary and peripheral arteries, reduces OPSS, AD and slightly - myocardial contractility, reduces afterload and myocardial oxygen demand. Improves coronary blood flow. Virtually does not have antiarrhythmic activity. Do not depress the conductivity of the myocardium.
PHARMACOKINETICS
When ingested quickly absorbed from the digestive tract. It is metabolized by the "first pass" through the liver. Binding with proteins is 92-98%. Metabolized in the liver with the formation of inactive metabolites. T 1/2 - about 2 hours. It is excreted mainly by kidneys in the form of metabolites and in trace amounts in unchanged form; 20% is excreted through the intestines in the form of metabolites.
INDICATIONS
Preventive maintenance of attacks of a stenocardia (including vasospastic angina), in some cases - a cupping of attacks of a stenocardia; arterial hypertension, hypertensive crises; Raynaud's disease.
DOSING MODE
Individual. For oral administration, the initial dose is 10 mg 3-4 times / day. If necessary, the dose is gradually increased to 20 mg 3-4 times / day. In special cases (variant angina, severe arterial hypertension) for a short time the dose can be increased to 30 mg 3-4 times / day. To relieve the hypertensive crisis, as well as an attack of angina pectoris, it is possible to apply sublingually on 10-20 mg (rarely 30 mg).
In / in to stop an attack of angina or hypertensive crisis - 5 mg for 4-8 hours.
Intracoronary for the relief of acute spasms of the coronary arteries is administered with a bolus of 100-200 Ојg. When stenoses of large coronary vessels, the initial dose is 50-100 Ојg.
Maximum daily doses: when ingested - 120 mg, with IV in the introduction - 30 mg.
SIDE EFFECT
From the side of the cardiovascular system: hyperemia of the skin, sensation of heat, tachycardia, arterial hypotension, peripheral edema; rarely - bradycardia, ventricular tachycardia, asystole, increased attacks of angina pectoris.
On the part of the digestive system: nausea, heartburn, diarrhea; rarely - impaired liver function; in isolated cases - gingival hyperplasia. With prolonged use in high doses, there may be diarrheal symptoms, increased activity of hepatic transaminases, intrahepatic cholestasis.
From the side of the central nervous system and peripheral nervous system: headache. With prolonged use in high doses, paresthesia, muscle pain, tremor, light vision disorders, sleep disturbances are possible.
On the part of the hematopoiesis system: in isolated cases - leukopenia, thrombocytopenia.
On the part of the urinary system: an increase in daily diuresis. With prolonged use in high doses, there may be impaired renal function.
From the endocrine system: in isolated cases - gynecomastia.
Allergic reactions: skin rash.
Local reactions: with intravenous administration, burning at the injection site is possible.
Within 1 min after intracoronary administration, there may be a negative inotropic effect of nifedipine, an increase in heart rate, arterial hypotension; these symptoms gradually disappear after 5-15 minutes.
CONTRAINDICATIONS
Arterial hypotension (systolic blood pressure below 90 mm Hg), collapse, cardiogenic shock, severe heart failure, severe aortic stenosis; hypersensitivity to nifedipine.
PREGNANCY AND LACTATION
Adequate and strictly controlled safety studies of nifedipine in pregnancy have not been conducted. The use of nifedipine in pregnancy is not recommended.
Because nifedipine is excreted in breast milk, its use during lactation should be avoided or breastfeeding discontinued during treatment.
In experimental studies , embryotoxic, fetotoxic and teratogenic effects of nifedipine have been identified.
APPLICATION FOR FUNCTIONS OF THE LIVER
For violations of kidney function Nifedipine should be used only in a clinic under the strict supervision of a doctor. In patients with impaired renal function, nifedipine should be avoided in high doses.
APPLICATION FOR VIOLATIONS OF THE FUNCTION OF KIDNEYS
In case of violations of liver function Nifedipine should be used only in a clinic under the strict supervision of a doctor. In patients with impaired liver function, nifedipine should be avoided in high doses.
APPLICATION IN ELDERLY PATIENTS
In elderly patients, the reduction of cerebral blood flow is more likely due to severe peripheral vasodilation.
SPECIAL INSTRUCTIONS
Nifedipine should be used only in a clinic under the strict supervision of a physician with acute myocardial infarction, severe cerebral circulation disorders, diabetes mellitus, violations of liver and kidney function, malignant hypertension and hypovolemia, as well as in patients undergoing hemodialysis. In patients with impaired liver and / or kidney function, nifedipine should be avoided in high doses. In elderly patients, the reduction of cerebral blood flow is more likely due to severe peripheral vasodilation.
When ingestion to accelerate the effect of nifedipine can be chewed.
If you have pain on the sternum, nifedipine should be discarded. To cancel nifedipine should be gradual, because with sudden discontinuation (especially after long-term treatment) may develop withdrawal syndrome.
When intracoronary administration in the presence of stenosis of two vessels, nifedipine should not be introduced into the third open vessel because of the danger of pronounced negative inotropic action.
During the course of treatment, do not allow alcohol because of the risk of excessive blood pressure lowering.
Impact on the ability to drive vehicles and manage mechanisms
At the beginning of treatment, it is necessary to avoid driving vehicles and other potentially dangerous activities requiring rapidity of psychomotor reactions. In the course of further treatment, the degree of restriction is determined depending on the individual tolerability of nifedipine.
DRUG INTERACTION
With simultaneous use with antihypertensive drugs, diuretics, phenothiazine derivatives, the antihypertensive effect of nifedipine is enhanced.
With simultaneous use with anticholinergic drugs, memory and attention disorders may occur in elderly patients.
With simultaneous application with beta-adrenoblockers, it is possible to develop severe arterial hypotension; in some cases - the development of heart failure.
With simultaneous use with nitrates, the antianginal effect of nifedipine increases.
With simultaneous use with calcium preparations, the effectiveness of nifedipine decreases due to antagonistic interaction caused by an increase in the concentration of calcium ions in the extracellular fluid.
The cases of development of muscle weakness with simultaneous application with magnesium salts are described.
With simultaneous use with digoxin, the digoxin release from the body can be slowed down and, consequently, its concentration in the blood plasma increases.
With simultaneous use with diltiazem increases antihypertensive effect.
With simultaneous application with theophylline, changes in the concentration of theophylline in the blood plasma are possible.
Rifampicin induces the activity of liver enzymes, speeding up the metabolism of nifedipine, which leads to a decrease in its effectiveness.
With simultaneous use with phenobarbital, phenytoin, carbamazepine, the concentration of nifedipine in the blood plasma decreases.
There have been reports of an increase in the concentration of nifedipine in the blood plasma and an increase in its AUC with simultaneous use with fluconazole, itraconazole.
With simultaneous use with fluoxetine may increase the side effect of nifedipine.
In some cases, with concomitant use with quinidine, a decrease in the concentration of quinidine in the blood plasma is possible, and with the withdrawal of nifedipine, a significant increase in the concentration of quinidine is possible, which is accompanied by an extension of the QT interval on the ECG.
Cimetidine and, to a lesser extent, ranitidine, increase the concentration of nifedipine in the blood plasma and, thus, enhance its antihypertensive effect.
Ethanol can enhance the action of nifedipine (excessive arterial hypotension), which causes dizziness and other unwanted reactions.
