active substance: azithromycin (azithromycin)
1 tablet contains azithromycin dehydrate equivalent to azithromycin 250 mg
Auxiliary substances: microcrystalline cellulose, sodium croscarmellose, sodium lauryl sulfate, povidone K 90, talc, magnesium stearate, coating Opadry 04B52069 yellow: gipromelloza, titanium dioxide (E 171), quinoline yellow (E 104), polyethylene glycols.
Basic physico-chemical properties: capsule-like tablets coated in yellow with the logo "a 250" on the one hand and smooth on the other.
Antibacterial agents for systemic use. Macrolides, lincosamide and streptogramin. Azithromycin. ATC code J01F A10.
Azithromycin is a macrolide antibiotic that belongs to the group of azalides. The molecule is formed by the introduction of nitrogen atom in the lactone ring erythromycin A.
The mechanism of action of azithromycin is inhibition of bacterial protein synthesis by binding to 50 S subunit of ribosomes and the inhibition of the translocation of peptides.
The mechanism of resistance.
Complete cross-resistance exists among Streptococcus beidajie, beta-hemolytic Streptococcus of group A, Enterococcus faecalis and Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus (МRSА), to erythromycin, azithromycin, other macrolides and lincosamides.
The prevalence of acquired resistance can be different depending on the location and time for the selected species, so local information about resistance is needed especially in the treatment of severe infections. If necessary, you can seek expert advice, if the local prevalence of resistance is such, when the effectiveness of the drug in the treatment of at least some types of infections is doubtful.
Spectrum of antimicrobial action of azithromycin.
Usually sensitive species
Aerobic gram-positive bacteria
Staphylococcus aureus methicillin-sensitive
Beidajie Streptococcus, penicillin-sensitive
Aerobic gram-negative bacteria
Species for which acquired resistance may be a problem
Aerobic gram-positive bacteria
Streptococcus pneumonia with intermediate sensitivity to penicillin and penicillin-resistant
Aerobic gram-positive bacteria
Staphylococci МRSА, МRSЕ *
The group Bacteroides fragilis Bacteroides
* Methicillin-resistant Staphylococcus aureus has a very high prevalence of acquired resistance to macrolides and was listed here for a rare sensitivity to azithromycin.
Bioavailability after oral administration is approximately 37%. The maximum concentration in the serum is achieved 2-3 hours after taking the drug. When taking azithromycin is distributed throughout the body. In pharmacokinetic studies, it was shown that the concentration of azithromycin in tissues is much higher (50 times) than in blood plasma, which indicates a strong binding of the drug with tissues.
Linking blood plasma proteins varies according to plasma concentration and ranges from 12% at 0.5 mg/ml up to 52% at 0.05 mg/ml in the serum. The volume of distribution at steady state (V ss ) was 31.1 l/kg.
The final period of plasma half-life fully reflects the half-life of tissues for 2-4 days.
Approximately 12% of the dose of azithromycin are unchanged in the urine for the next 3 days. Very high concentrations of unchanged azithromycin were found in human bile. Also in the bile was detected 10 metabolites, which were formed by N - and O-demethylation, hydroxylation of the rings desosamine and aglycone and splitting cladinose conjugate. Comparison of the results of liquid chromatography and microbiological analyses showed that the metabolites of azithromycin are not microbiologically active.
Infections caused by microorganisms sensitive to azithromycin:
ENT-organs (bacterial pharyngitis/tonsillitis, sinusitis, otitis media);
respiratory infections (bacterial bronchitis, community-acquired pneumonia)
infections of the skin and soft tissues: migrating erythema (the initial stage of Lyme disease), erysipelas, impetigo, secondary pyodermatosis;
sexually transmitted infections: uncomplicated and complicated urethritis/cervicitis caused by Chlamydia trachomatis.
Hypersensitivity to azithromycin, erythromycin or any macrolide or ketolide antibiotic, or to any other component of the drug.
Through the theoretical possibility of ergotism, azithromycin should not be prescribed simultaneously with the derivatives of controversial.
Interaction with other medicinal products and other forms of interaction
Azithromycin should be administered cautiously to patients along with other medications that may extend the q-interval.
Antacids. In the study of the effect of the simultaneous use of antacids on the pharmacokinetics of azithromycin, in General, there were no changes in bioavailability, although plasma peak concentrations of azithromycin decreased by about 25%. Azithromycin should be taken at least 1:00 before or 2:00 after taking antacid.
Cetirizine. In healthy volunteers with the simultaneous use of azithromycin for 5 days with cetirizine 20 mg in equilibrium, there were no phenomena of pharmacokinetic interaction or significant changes in THE Qt interval.
Didanosine. With simultaneous use of daily doses of 1200 mg of azithromycin with didanosine, no effect was found on the pharmacokinetics of didanosine compared to placebo.
Digoxin. It was reported that concurrent use of macrolide antibiotics, including azithromycin, and substrates of P-glycoprotein, such as digoxin, leading to increased level of the substrate of P-glycoprotein in the blood serum. Therefore, the simultaneous use of azithromycin and digoxin should take into account the possibility of increasing the concentration of digoxin in serum.
Zidovudine. A single dose 1000 mg and 1200 mg or 600 mg multiple doses of azithromycin did not affect the plasma pharmacokinetics or urinary excretion of zidovudine or its glucuronic metabolites. However, the use of azithromycin increased the concentrations of phosphorylated zidovudine, clinically active metabolite, in mononuclear cells in peripheral blood. The clinical significance of these data has not been clarified, but may be useful for patients.
Horns. Given the theoretical possibility of ergotism, the simultaneous introduction of azithromycin with ergot derivatives is not recommended.
Azithromycin has no significant interaction with the liver system of cytochrome P450. It is believed that the drug has no pharmacokinetic drug interaction, observed with erythromycin and other macrolides. Azithromycin does not cause induction or inactivation via cytochrome P450 cytochrome-metabolite complex.
Pharmacokinetic studies of the use of azithromycin and the following drugs were conducted, the metabolism of which largely occurs with the participation of cytochrome P450.
Atorvastatin. The simultaneous use of atorvastatin (10 mg/day) and azithromycin (500 mg/day) did not cause changes in plasma concentrations of atorvastatin (based on the analysis of inhibition of COA-reductase NMG).
Carbamazepine. In the study of pharmacokinetic interaction in healthy volunteers azithromycin did not show a significant effect on plasma levels of carbamazepine or its active metabolites.
Cimetidine. In the pharmacokinetic study of the effect of a single dose of cimetidine taken 2:00 before taking azithromycin on the pharmacokinetics of azithromycin, no changes in the pharmacokinetics of azithromycin were observed.
Oral anticoagulants, like coumarin. In the study of pharmacokinetic interaction, azithromycin did not change the anticoagulant effect of a single dose of 15 mg of warfarin intended for healthy volunteers. There is evidence of the potentiation