Zithromax is a broad-spectrum antibacterial drug. It belongs to the group of macrolides-azalides, acts bacteriostatically. By binding to the 50S subunit of ribosomes, it inhibits the peptide translocase at the translation stage, inhibits protein synthesis, slows the growth and bacteria reproduction. It has a bactericidal effect in high concentrations. It acts on extra- and intracellularly located pathogens. Microorganisms may be initially resistant to the action of the antibiotic or may become resistant to it.


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, incl. caused by atypical pathogens;
  • infections of the skin and soft tissues: ordinary acne of moderate severity, erysipelas, impetigo, secondarily infected dermatoses;
  • the initial stage of Lyme disease (borreliosis) – erythema migrans;
  • urinary tract infections caused by Chlamydia trachomatis (urethritis, cervicitis).

Dosage regimen

Zithromax is taken orally 1 time/day at 500 mg, regardless of food intake.

Adults (including older people) and children over 12 years old with body weight over 45 kg:

  • for infections of the upper and lower respiratory tract, ENT organs, skin and soft tissues: 500 mg 1 time/day for 3 days (course dose – 1.5 g).
  • acne vulgaris of moderate severity: 2 caps. 250 mg 1 time/day for 3 days, then 250 mg 2 times a week for 9 days. A course dose – 6.0 g.
  • erythema migrans: on the first day – 2 caps. 500 mg, then from the 2nd to the 5th day -500 mg daily. The course dose is 3.0 g.
  • infections of the genitourinary tract caused by Chlamydia trachomatis (urethritis, cervicitis): 2 caps. 500 mg.

Side effect

  • Digestive system: nausea, vomiting, diarrhea, abdominal pain, loose stools, flatulence, digestive upset, 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, photosensitivity, anaphylactic reaction (in rare cases, fatal), erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis.
  • Cardiovascular system: palpitations, arrhythmia, ventricular tachycardia, increased QT interval, bidirectional ventricular tachycardia.
  • Nervous system: dizziness/vertigo, headache, cramps, drowsiness, paresthesia, asthenia, insomnia, hyperactivity, aggressiveness, anxiety, nervousness.
  • Sensory organs: tinnitus, reversible hearing impairment up to deafness (when taking high doses for a long time), impaired perception of taste and smell.
  • Circulatory and lymphatic systems: thrombocytopenia, neutropenia, eosinophilia.
  • Musculoskeletal system: arthralgia.
  • Genitourinary system: interstitial nephritis, acute renal failure.
  • Other: vaginitis, candidiasis.


  • Severe hepatic and/or renal failure;
  • Children under 12 years old with a bodyweight of less than 45 kg (for this dosage form);
  • Breast-feeding;
  • Concomitant use with ergotamine and dihydroergotamine;
  • Hypersensitivity to antibiotics of the macrolide group.


  • Moderate hepatic and renal impairment;
  • Arrhythmias or a predisposition to arrhythmias;
  • Lengthening of the QT interval;
  • The combined use of terfenadine, warfarin, digoxin.

Pregnancy and lactation

Zithromax during pregnancy is recommended to be used only in cases when the expected benefits of taking it for the mother outweighs the potential risk to the fetus. During treatment with Zithromax, breastfeeding is arrested.

Use for impaired liver function

Contraindicated in severe liver failure. Use with caution in moderate hepatic impairment.

Use for impaired renal function

Contraindicated in severe renal failure. For patients with moderately impaired renal function (CC> 40 ml/min), dose adjustment is not required.

Use in children

Children under 12 years old with a bodyweight of less than 45 kg is a direct contraindication.

Missed dose and discontinuation

If you miss the dose of an antibiotic, the missed dose should be taken as early as possible, and subsequent doses should be taken at intervals of 24 hours. After discontinuation of Zithromax therapy, hypersensitivity reactions in some patients may persist for a long time. It may require specific therapy under physician supervision.


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

Treatment: symptomatic.

Drug interaction

  • Antacids do not affect the bioavailability of Zithromax 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 meals.
  • If necessary, combined use with cyclosporine is recommended to control the content of cyclosporine in the blood.
  • With the combined use of digoxin and Zithromax, it is necessary to control the concentration of digoxin in the blood, because many macrolides increase the absorption of digoxin in the intestine, thereby increasing its concentration in blood plasma.
  • If necessary, co-administration with warfarin, it is recommended to carefully monitor the prothrombin time.
  • The simultaneous administration of terfenadine and antibiotics of the macrolide class causes arrhythmia and lengthening of the QT interval. Based on this, the above complications cannot be excluded from the combined use of terfenadine and azithromycin.
  • With the combined use of azithromycin and zidovudine, azithromycin does not affect the pharmacokinetic parameters of zidovudine in blood plasma or the excretion of zidovudine by the kidneys and its glucuronidated metabolite. Nevertheless, the concentration of the active metabolite, phosphorylated zidovudine, in the mononuclear cells of peripheral vessels increases. The clinical significance of this evidence is unclear.
  • the toxic effect may occur with the simultaneous administration of macrolides with ergotamines and dihydroergotamine.