Isosorbide mononitrate - instructions for use, dose, side effects, contraindications

Antianginal effect of the drug is associated with the expansion of peripheral vessels, mainly venous. Vein dilatation leads to a decrease in venous return to the heart (reducing myocardial overload) and end-diastolic blood pressure. Expansion of the arterial vessels leads to a decrease in the total peripheral resistance and blood pressure, hence, to a decrease in postload on the heart. In turn, the reduction of pre- and post-loading on the heart leads to a decrease in the work of the heart and its need for oxygen. Direct expansion of the coronary vessels stimulates collateral circulation with redistribution of blood flow to the ischemic site of the myocardium.

The vasodilator effect of the drug is due to the action on the smooth muscle cells of the vessels with nitrogen oxide NO, which is released from isosorbide nitrate during metabolism. The identity of nitric oxide to the endothelial relaxing factor derived from the amino acid of L-arginine activates the cytosolic enzyme of intact vascular endothelium - guanylate cyclase, which contributes to the accumulation of cGMP.As a result, the calcium content in the cytosol of smooth muscle cells decreases, as a result of which the smooth muscles of the vessels are relaxed.

Antiaggregant activity is due to a decrease in platelet aggregation.

Spasmolytic effect extends to the smooth muscles of the internal organs, which leads to a decrease in the tone of the bronchi, intestines, bile ducts and ureters.

Pharmacokinetics:

After oral administration, the empty stomach is completely absorbed in the gastrointestinal tract. The maximum concentration in the blood plasma is achieved after 3.5 minutes. The connection with plasma proteins is less than 4%.

Antianginal effect after taking the drug inside develops after 1 hour, lasts up to 12 hours or more. Metabolism in the kidneys with the formation of two pharmacologically inactive glucuronides (the half-elution period of these compounds is 6-8 hours).

The half-life is 4-6 hours. Elimination by the kidneys.

Indications:

It is used to stop and prevent attacks of angina pectoris, including postinfarction; for the treatment of chronic congestive heart failure in combination with diuretics and cardiac glycosides.

ICD-10

IX.I20-I25.I20 Angina pectoris [angina pectoris]

IX.I20-I25.I25 Chronic ischemic heart disease

IX.I20-I25.I25.2 Postponed myocardial infarction

IX.I26-I28.I27 Other forms of pulmonary heart disease

IX.I30-I52.I50.0 Congestive heart failure

Contraindications:

Increased intracranial pressure, stroke, collapse, toxic pulmonary edema, angle-closure glaucoma, constrictive pericarditis, cardiac tamponade, marked violations of liver and kidney function, severe anemia, individual intolerance, children under 18 years of age.

Carefully:

Propensity to orthostatic hypotension.

Pregnancy and lactation:

Recommendations for FDA - Category C. Contraindicated in pregnancy and lactation.

Dosing and Administration:

Inside, the initial dose: 10-20 mg 2 times a day or 40-60 mg in the morning. If necessary, the dose rises to 20-40 mg twice a day. If there is an acute need, it is possible to increase the dose to 120-140 mg once a day.

The highest daily dose: 140 mg.

The highest single dose: 140 mg.

Side effects:

Central and peripheral nervous system: motor anxiety, dizziness, headache, attention disturbance.

Respiratory system: rarely - shortness of breath.

The system of hematopoiesis: hypocoagulation.

The cardiovascular system: sensation of fever, arterial hypotension, tachycardia, collapse.

Digestive system: nausea, vomiting, dry mouth, burning sensation of the tongue.

Organs of Senses: Visual Disorders.

Musculoskeletal system: stiffness of movements.

Dermatological reactions: skin rash.

Allergic reactions.

Overdose:

Orthostatic hypotension, hyperthermia, convulsions. With infusion in high doses, methhemoglobinaemia develops: cyanosis of the lips, nails and palms, tachypnea, sensation of pressure in the head.

Treatment: discontinuation of infusion, intravenous 1% methylene blue, dopamine and sympathomimetics. The patient is given a horizontal position with his legs raised, if blood pressure is not normalized, the volume of circulating blood is corrected, artificial ventilation, produce an exchange blood transfusion.

Interaction:

Potentiates the effect of antihypertensive drugs, weakens the action of norepinephrine and epinephrine.

With the combined intake of alcohol, a collapse develops.

Special instructions:

To prevent hypotension and "nitrate" headache, treatment should begin with the minimum recommended dose. With prolonged use, there is an addiction that can be cross-over. In order to prevent the development of addiction, it is recommended after 3-6 weeks of regular intake to take a break for 3-5 days.

Patients taking isosorbide nitrate are advised to exercise caution when driving vehicles and working with moving machinery.

Instructions

Isosorbide mononitrate (Isosorbidi mononitras)