Azithromycin(capsules 0,25)

Сapsulae Azithromycini 0,25

 

International nonproprietary name

Azithromycin.

Azithromycin.

Pharmacotherapeutic group

Anti-infectives. Antibiotics - макролиды.

Structure

1 capsule contains 250 mg of Azithromycin.

Pharmacological action

Pharmacodynamics

Azithromycin (9-deoxo-9а-aza-9а-methyl-9а-homoerythromycin) has antibacterial (bacteriostatic) action. It binds with 50S subunit of ribosomes, inhibits peptide translocase at a stage of translation and suppresses protein biosynthesis, inhibiting growth and multiplication of bacteria, the bactericidal effect is possible at high concentration.

Spectrum of Azithromycin antimicrobial action is wide, including gram-positive (Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalctiae, Streptococcus pneumoniae, Streptococcus pyogenes, streptococcuses of groups C, F, G, Streptococcus viridans), except for strains resistant to erythromycin, and gram-negative (Haemophilus influenzae, Moraxella catarrhalis, Bordetella pertussis, Bordetella parapertussis, Campylobacter jejuni, Legionella pneumophila, Neisseria gonorrhoeae, Gardnerella vaginalis) microorganisms, anaerobic bacteria (Bacteroides bivius, Peptostreptococcus spp., Peptococcus, Clostridium perfringens), chlamydias (Chlamydia trachomatis, Chlamydia pneumoniae), micobacteria (Мycobacteria avium complex), mycoplasmas (Mycoplasma pneumoniae), ureaplasmas (Ureaplasma urealyticum), spirochetes (Treponema pallidum).

Pharmakokinetics

It is steady in acidic medium, lipophilic. Quickly absorbed in gastrointestinal tract. After single administration of 500 mg the bioavailability is 37 %, maximum concentration in blood (0,4 mg/l) is reached in 2-3 hours. Intake of food and alcohol reduces rate and completeness of absorption. In case of preparation administration soon after food intake the maximal concentration in a blood (Cmax) decreases approximately in 50 %. Apparent volume of distribution is 31,1 l/kg, binding with proteins is in inverse proportion to concentration in blood and amounts to 7-50 %. The period of half-elimination Т1/2is 68 hours. The stable level in plasma is reached in 5-7 days.

Azithromycin easily passes through histohematogenous barriers and enters in tissues. It is also transported by phagocytes, polymorphonuclear leucocytes and macrophages to a place of infection where it is released at presence of bacteria. Passes through cells membranes (effective at the infections caused by intracellular agents). Concentration in tissues and cells is in 10-50 time higher than in plasma, and in the nidus of infection in 24-34 % higher than in healthy tissues. The high level of concentration is kept in tissues within 5-7 days after last administration. In a liver Azithromycin demethylates; and resultant metabolites are inactive. Plasma clearance is 630 ml/min. About 50 % of the administrated dose of Azithromycin are eliminated with urine in not changed form, 6 % are eliminated with bile. In elderly men (65-85 years old) the parameters of pharmakokinetics do not change, in elderly women – Cmax is increased (in 30-50 %). In children in the age of 1-5 years old the maximal concentration in bloods, the period of half-elimination and AUC parameter are reduced in comparison with adults.

Indications 

Infections of upper (bacterial pharyngitis and tonsillitis) and inferior (bacterial exacerbation of chronic obstructive pneumonia, interstitial and alveolar pneumonia, bacterial bronchitis) respiratory tract, an ENT-organs (angina, otitis media, laryngitis and sinusitis), genitourinary system (urethritis and/or cervicitis), skins and soft tissues (erypsipelas, impetigo, secondary infected dermatoses), a chronic stage of migratory erythema (initial stage of Lime disease), diseases of stomach and duodenum, associated with Helicobacter pylori.

Dosage and method of administration

The medicine is taken 1 time day in 1 hour prior to meal or in 2 hours after meal. In the first day of treatment Azithromycin  is administrated to adults in a dose of 0,5 g/day, from 2 to 5 days -- 0,25 g/day. Course dose is 1,5 g. At urogenital diseases – single dose of 1 g, at Lime disease - 1 gin the first day, from 2 to 5 days - per 0,5 g(course dose is 3 g). At diseases of stomach and duodenum, associated with Helicobacter pylori, the intake is 1 g/day for 3 days in the structure of combined therapy. For children elder than 12 months in the first day of therapy - 10 mg/kg of body weight 1 time a day, then during 4 days of therapy per 5 mg/kg/day or per 10 mg/kg/day for 3 days (course dose is 30 mg/kg of body weight). At Lime disease - in the first day per 20 mg/kg/day, from 2 to 5 days - per 10 mg/kg/day. In case of 1 dose of the preparation omission it is necessary to take the missed dose as soon as possible, and the subsequent dose is administrated after 24 hours interval.

Special indications

Elderly people and patients with impaired kidneys function do not have necessity to change a dosage.

Side effects

The nausea, vomiting, diarrhea, constipation, meteorism, abdominal pain, melena, cholestatic icterus, stethalgia, fatigue, palpitation, headache, giddiness, sleepiness, sleeplessness, conjunctivitis, nephritis, vaginitis, neutropenia or neutrophilia, reversible moderate increase of hepatic enzymes activity, pseudomembranous colitis, candidiasis, photosensitization, dermal eruption, Quincke's edema, eosinophilia, and in children, except for the above mentioned -- hyperkinesia.

Contraindications

Hypersensitivity (including another macrolides), serious disorders of liver function, pregnancy, lactation (for the period of treatment it is necessary to stop breast feeding).

Precautions

Administrated with care at the expressed disorders of kidneys function, disorders of liver function (especially for children), at cardiac arrhythmias (ventricular arrhythmias and QT interval elongation are possible). After  withdrawal of treatment the reaction of hypersensitivity in some patients can remain, in this case the specific therapy under observation of the doctor is necessary.

Interaction with other preparations

Antacids reduce absorption of Azithromycin (the interval not less than 2 hours is recommended between intakes).

In spite of the fact that Azithromycin inhibits cytochrome Р450 more weakly than erythromycin, the careful control of patients condition over simultaneous administration of the preparations metabolized in a liver is required. Azithromycin strengthens action of ergot alkaloids and Dihydroergotamine. It reduces secretion, increases concentration in plasma and toxicity of Cycloserine, indirect anticoagulants, Methylprednisolone, Felodipin, the medical products exposed to microsomal oxidation (Karbamazepine, ergot alkaloids, Valproate acid, Hexobarbital, Phenytoin, Disopyramidume, Bromocriptine, Theophylline, etc. xanthine derivatives, peroral hypoglycemic medical products). Lincosamides reduce its efficiency, Tetracyclinum and Chloramfenicol increases it. It is incompatible pharmaceutically with heparin.

It is dangerous to combine Azithromycin with the preparations extending interval QT on EKG.

Overdosage

Signs: temporary loss hearing, nausea, vomiting, diarrhea.

Treatment: symptomatic (the specific antidote is absent).

The form of release

Hard gelatin capsules of 250 mg. 6 capsules in a blister.