Dexamethasone, tablets 0.5 mg 56 pcs

Dexamethasone is a synthetic glucocorticosteroid (GCS), methylated fluoroprednisolone derivative. It has anti-inflammatory, anti-allergic, desensitizing, immunosuppressive, antishock and antitoxic effects.

Inhibits secretion of thyroid hormone and follicle stimulating hormone.

Increases central nervous system excitability, decreases the number of lymphocytes and eosinophils, increases the number of erythrocytes (stimulates erythropoietin production).

Interacts with specific cytoplasmic receptors and forms a complex penetrating into cell nucleus, stimulates synthesis of matrix ribonucleic acid (mRNA); the latter induces formation of proteins, including lipocortin, mediating cellular effects. Lipocortin inhibits phospholipase A2, inhibits the release of arachidonic acid and inhibits the synthesis of endoperoxins, prostaglandins, leukotrienes, contributing to the processes of inflammation, allergy and others.

Effect on protein metabolism: reduces the amount of protein in the plasma (at the expense of globulins) with an increase in albumin/globulin ratio, increases the synthesis of albumin in the liver and kidneys; increases protein catabolism in muscle tissue.

Effect on lipid metabolism: increases the synthesis of higher fatty acids and triglycerides, redistributes fat (fat accumulation mainly in the shoulder girdle, face, abdomen), leads to hypercholesterolemia.

Effect on carbohydrate metabolism: increases absorption of carbohydrates from the gastrointestinal tract (GIT), increases the activity of glucose-6-phosphatase, leading to increased glucose flow from the liver into the blood, increases the activity of phosphoenolpyruvate carboxylase and aminotransferase synthesis, which leads to activation of gluconeogenesis.

Effect on water-electrolyte metabolism: it retains sodium ions and water in the body, stimulates excretion of potassium ions (mineralocorticosteroid activity), reduces the absorption of calcium ions from the GIT, “washes” calcium ions from the bones, increases excretion of calcium ions by kidneys.

Anti-inflammatory activity is associated with inhibition of eosinophils release of inflammatory mediators, induction of lipocortin formation and reduction of hyaluronic acid-producing mast cells number, capillary permeability reduction, stabilization of cell and organelle membranes (especially lysosomal).

. An antiallergic effect is produced due to suppression of allergy mediators synthesis and secretion, inhibition of histamine and other bioactive substances release from sensitized mast cells and basophils, reduction of circulating basophils number, suppression of lymphoid and connective tissue development, reduction of T- and B-lymphocytes quantity, mast cells, reduction of effector cells sensitivity to allergy mediators, suppression of antibody formation, change in the organism immune response.

In chronic obstructive pulmonary disease action is mainly based on inhibition of inflammatory processes, inhibition or prevention of mucous membrane edema, inhibition of eosinophilic infiltration of submucous layer of bronchial epithelium, deposition of circulating immune complexes in bronchial mucosa, and inhibition of mucous membrane erosion and desquamation. It increases sensitivity of small and medium caliber bronchial beta-adrenoreceptors to endogenous catecholamines and exogenous sympathomimetics, decreases bronchial secretion viscosity by inhibiting or reducing its production.

Antishock and antitoxic action is associated with increase of arterial pressure (due to increase in concentration of circulating catecholamines and restoration of adrenoreceptors sensitivity to them as well as vasoconstriction), reduction of vascular wall permeability, membrane-protective properties, activation of liver enzymes involved in metabolism of endo- and xenobiotics.

Immunosuppressive effect is caused by inhibition of cytokine release (interleukin-1, interleukin-2, interferon gamma) from lymphocytes and macrophages.

Inhibits the synthesis and secretion of adrenocorticotropic hormone (ACTH), and secondary the synthesis of endogenous GCS.
Peculiarities of action are significant inhibition of pituitary function and almost complete absence of mineralocorticosteroid activity. Doses of 1-1.5 mg/day inhibit adrenal cortex; biological half-life is 32-72 hours (duration of inhibition of hypothalamic-pituitary-adrenal cortical layer system).

In terms of glucocorticoid activity 0.5 mg of dexamethasone corresponds to approximately 3.5 mg of prednisolone, 15 mg of hydrocortisone or 17.5 mg of cortisone for oral dosage forms.

Pharmacokinetics

Absorption

After oral administration is quickly and completely absorbed, the maximum concentration of dexamethasone in blood plasma is 1-2 hours.

Distribution

In the blood it is bound (60 – 70%) with the specific carrier protein – transcortin. Easily passes through histohematic barriers (including the blood-brain barrier and the placental barrier).

Metabolism

Metabolized in liver (mainly by conjugation with glucuronic and sulfuric acids) to inactive metabolites.

Excretion

Excreted by the kidneys (a small amount of dexamethasone penetrates into breast milk). The elimination half-life is 3-5 hours.

Indications

Active ingredient

Composition

How to take, the dosage

Interaction

Special Instructions

Contraindications

Side effects

Overdose

Dose-dependent side effects may increase, with the exception of allergic reactions. The dose of dexamethasone should be reduced.

Treatment: symptomatic.

Pregnancy use

Similarities