Last reviewed 2026-04-22 · How we verify

Azithromycin on Day 8

Azithromycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, thereby stopping bacterial growth.

Azithromycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, thereby stopping bacterial growth. Used for Community-acquired pneumonia, Acute bacterial sinusitis, Acute otitis media.

At a glance

Mechanism of action

Azithromycin is a macrolide antibiotic that binds to bacterial 23S rRNA within the 50S ribosomal subunit, preventing peptide bond formation and elongation of the bacterial polypeptide chain. This bacteriostatic action halts protein synthesis and allows the immune system to clear the infection. It also has immunomodulatory properties that may reduce inflammation in certain conditions.

Approved indications

• Community-acquired pneumonia
• Acute bacterial sinusitis
• Acute otitis media
• Pharyngitis/tonsillitis
• Bronchitis
• Skin and soft tissue infections
• Sexually transmitted infections (chlamydia, gonorrhea)

Common side effects

• Diarrhea
• Nausea
• Abdominal pain
• Vomiting
• QT prolongation
• Hepatotoxicity
• Allergic reactions

Key clinical trials

• An Adaptive Multi-arm Trial to Improve Clinical Outcomes Among Children Recovering From Complicated SAM (PHASE3)
• Randomized, Embedded, Multifactorial Adaptive Platform Trial for Community- Acquired Pneumonia (PHASE3)
• Randomised Evaluation of COVID-19 Therapy (PHASE3)
• Eucalyptus Oil as Adjuvant Therapy for Coronavirus Disease 19 (COVID-19) (PHASE2)
• Efficacy of Canrenone as add-on Treatment in Moderate to Severe ARDS in COVID-19 (PHASE2)
• COVID-19 Study at the Russian Clinical and Research Center of Gerontology of the Pirogov RNRMU
• Experimental Human Infection With Neisseria Gonorrhoeae (LptA Trial) (PHASE1)
• Cholera Anti-Secretory Treatment Trial (PHASE2)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.