Azithromycin pills 500mg №3

Mechanism of action

A broad-spectrum antibacterial drug from the group of macrolide-azalides, bacteriostatic. By binding to the 50S subunit of ribosomes, it inhibits peptide translocation at the translation stage, inhibits protein synthesis, slows the growth and reproduction of bacteria, has a bactericidal effect in high concentrations. Acts on extra-and intracellularly located pathogens.

Microorganisms can be initially resistant to the action of the antibiotic or can become resistant to it.

The scale of sensitivity of microorganisms to azithromycin (Minimum inhibitory concentration (MIC), mg / l):

Sensitive:

aerobic gram-positive microorganisms: Staphylococcus aureus (methylcylline-sensitive), Streptococcus pneumoniae (penicillin-sensitive), Streptococcus pyogenes;

aerobic gram-negative microorganisms: Haemophilus influenzae, Haemophilus parainfluenzae, Legionella pneumophila, Moraxella catarrhalis, Pasteurella multocida, Neisseria gonorrhoeae;

anaerobic microorganisms: Clostridium perfringens, Fusobacterium spp., Prevotella spp., Porphyromonas spp.;

Other: Chlamydia trachomatis, Chlamydia pneumoniae, Chlamydia psittaci, Mycoplasma pneumoniae, Mycoplasma hominis, Borrelia burgdoferi.

Moderately sensitive or insensitive:

aerobic gram-positive microorganisms: Streptococcus pneumoniae (moderately sensitive or resistant to penicillin).

Resistant to:

aerobic gram-positive microorganisms: Enterococcus faecalis, Staphylococci spp. (methicillin-resistant), Staphylococus aureus (including methicillin-sensitive strains), Staphylococus pneumoniae, Staphylococcus spp. group A (beta-hemolytic). Azithromycin is not active against strains of gram-positive bacteria that are resistant to Erythromycin.

anaerobes:

Bacteroides fragilis group.

Pharmacokinetics

After oral administration, azithromycin is well absorbed and quickly distributed in the body. Bioavailability after a single dose0.5 g - 37% (“first pass” effect through the liver), C_max after oral administration, 0.5 g - 0.4 mg / l, the time to reach the maximum concentration (TC_max) - 2-3 hours

The concentration in tissues and cells is 10-50 times higher than in serum. V_d - 31.1 l / kg, binding to plasma proteins is inversely proportional to the concentration in the blood and leaves 7-50%.

Azithromycin is acid-resistant, lipophilic. It easily passes through histohematogenous barriers, penetrates well into the respiratory tract, urinary organs and tissues, including into the prostate gland, skin and soft tissue. Phagocytes (polymorphonuclear leukocytes and macrophages) are also transported to the site of infection, where they are released in the presence of bacteria. It penetrates cell membranes and creates high concentrations in them, which is especially important for the eradication of intracellularly located pathogens. In the foci of infection, concentrations are 24–34% higher than in healthy tissues and correlate with the severity of the inflammatory process. It is stored in effective concentrations for 5-7 days after the last dose.

In the liver it is demethylated, the resulting metabolites are inactive.CYP3A4, CYP3A5, CYP3A7 isoenzymes are involved in azithromycin metabolism, of which it is an inhibitor. Plasma clearance - 630 ml / min: T_1/2 between 8 and 24 h after ingestion - 14-20 h, T_1/2 in the range from 24 to 72 hours - 41 hours

More than 50% of azithromycin is excreted by the intestine unchanged, 6% by the kidneys. Food intake substantially alters pharmacokinetics C_max increases (by 31%), AUC does not change.

In elderly men (65-85 years), pharmacokinetic parameters do not change, in women increases C_max (30-50%).

Indications

Infectious and inflammatory diseases caused by microorganisms sensitive to the drug:

- infections of the upper respiratory tract and ENT organs: pharyngitis, tonsillitis, sinusitis, otitis media;

- lower respiratory tract infections: acute bronchitis, exacerbation of chronic bronchitis, pneumonia, including caused by atypical pathogens;

- infections of the skin and soft tissues: common acne of moderate severity, erysipelas, impetigo, secondarily infected dermatosis;

- the initial stage of Lyme disease (borreliosis) - erythema migrans (erythema migrans);

- urinary tract infections caused by Chlamydia trachomatis (urethritis, cervicitis).

Dosage and administration

Azithromycin is taken orally 1 time / day by 500 mg, regardless of the meal.

Adults (including the elderly) and children over 12 years old weighing over 45 kg

At infections of the upper and lower respiratory tract, ENT organs, skin and soft tissues: 500 mg 1 time per day for 3 days (course dose - 1.5 g).

At common acne moderate severity: 2 caps. 250 mg 1 time / day for 3 days, then 250 mg 2 times a week for 9 days. Heading dose - 6.0 g.

At erythema migrans: on the first day at the same time 2 caps. 500 mg, then from the 2nd to the 5th day, 500 mg daily. Course dose 3.0 g.

At urinary tract infections caused by Chlamydia trachomatis (urethritis, cervicitis): simultaneously 2 caps. 500 mg.

Appointment to patients with renal impairment: for patients with moderate renal impairment (CC> 40 ml / min), correction is not required.

Side effect

Gastrointestinal: nausea, vomiting, diarrhea, abdominal pain, diarrhea, flatulence, indigestion, anorexia, constipation, discoloration of the tongue, pseudomembranous colitis, cholestatic jaundice, hepatitis, changes in laboratory parameters of liver function, liver failure, liver necrosis (possibly fatal ).

Allergic reactions: itching, skin rashes, angioedema, urticaria, photosensitization, anaphylactic reaction (in rare cases with fatal outcome), erythema multiforme, Stevens-Johnson syndrome, toxic epidermal spritis.

Cardiovascular: feeling of heartbeat, arrhythmia, ventricular tachycardia, an increase in the QT interval, bidirectional ventricular tachycardia.

Nervous system: dizziness / vertigo, headache, convulsions, drowsiness, paresthesia, asthenia, insomnia, hyperactivity, aggressiveness, anxiety, nervousness.

Special senses: tinnitus, reversible hearing impairment up to deafness (when taking high doses for a long time), impaired taste and smell.

From the circulatory and lymphatic systems: thrombocytopenia, neutropenia, eosinophilia.

Musculoskeletal system: arthralgia.

From the genitourinary system: interstitial nephritis, acute renal failure.

Other: vaginitis, candidiasis.

Contraindications

- severe hepatic and / or renal failure;

- children's age up to 12 years old with a body weight less than 45 kg (for this dosage form);

- breast-feeding;

- simultaneous intake with ergotamine and dihydroergotamine;

- hypersensitivity to macrolide antibiotics.

WITH caution

- moderate violations of the liver and kidneys;

- with arrhythmias or susceptibility to arrhythmias and prolongation of the QT interval;

- with the combined use of terfenadine, Warfarin , Digoxin.

Use during pregnancy and lactation

Azithromycin during pregnancy is recommended only in cases where the expected benefit from its reception for the mother outweighs the potential risk to the fetus.

During azithromycin treatment, breastfeeding is suspended.

Application for violations of the liver

Contraindicated in severe liver failure. Use with caution in moderate violations of the liver.

Application for violations of kidney function

Contraindicated in severe renal failure.

For patients with moderate renal impairment (CC> 40 ml / min), correction is not required.

Use in children

Contraindications for this dosage form - children's age up to 12 years old with a body weight less than 45 kg.

Use in elderly patients

Assign adults (including the elderly)

special instructions

In the case of skipping the antibiotic, the missed dose should be taken as early as possible, and subsequent doses taken at intervals of 24 hours.

After discontinuation of azithromycin therapy, hypersensitivity reactions in some patients may persist for a long time and may require specific therapy under the supervision of a physician.

Influence on ability to drive motor transport and control mechanisms

Given the likelihood of side effects from the central nervous system, caution should be exercised when driving and working with machinery.

Overdose

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

Treatment: symptomatic.

Drug interaction

Antacids do not affect the bioavailability of azithromycin, but reduce the maximum concentration in the blood by 30%, so the drug should be taken at least 1 hour before or 2 hours after taking these drugs and food.

When used parenterally, azithromycin does not affect the concentration of cimetidine, efavirenz, Fluconazole , indinavir, midazolam, triazolam, co-trimoxazole (sulfamethoxazole + trimethoprim) in the joint use, but do not exclude the possibility of such interactions when prescribing azithromycin for oral administration.

If necessary, the joint use with cyclosporine is recommended to control the content of cyclosporine in the blood.

When combined with digoxin and azithromycin, it is necessary to control the concentration of digoxin in the blood, since Many macrolides increase digoxin absorption in the intestine, thereby increasing its concentration in the blood plasma.

If necessary, the joint reception with warfarin is recommended to carefully monitor the prothrombin time.

Simultaneous use of terfenadine and macrolide-class antibiotics causes arrhythmia and prolongation of the QT interval. Based on this, it is impossible to exclude the above complications when co-administering terfenadine and azithromycin. Since there is a possibility of inhibiting CYP3A4 isoenzyme azithromycin in parenteral form with a joint