-5%
Erythromycin 250 inhibits bacterial protein synthesis via binding to the 50S ribosomal subunit, blocking translocation.
- Acid-sensitive; given as stable esters.
- Distribution: Widely distributed, crosses the placenta, excreted in breast milk.
- t½: 1.2–4 h (up to 5 h in renal impairment).
- Excretion: Mostly in bile; 5–15% via urine.
Effective in a wide range of infections:
- Upper respiratory: Tonsillitis, peritonsillar abscess, pharyngitis, laryngitis, sinusitis, secondary infections in colds & influenza.
- Lower respiratory: Tracheitis, acute & chronic bronchitis.
- Ear: Otitis media/externa, mastoiditis.
- Eye: Blepharitis, trachoma.
- Skin/Soft tissue: Boils, carbuncles, impetigo, abscesses, acne, paronychia, cellulitis, erysipelas.
- GI: Cholecystitis, staphylococcal enterocolitis.
- Prophylaxis: Pre/post-operative, trauma, burns, and rheumatic fever.
- Other: Osteomyelitis, diphtheria, scarlet fever, whooping cough.
- Microbial Spectrum
- Gram (+): Cocci, bacilli.
- Gram (–): Neisseria spp., Haemophilus influenzae, Bordetella pertussis.
- Others: Mycoplasma pneumoniae, Legionella pneumophila, Bacteroides spp., Fusobacterium, Chlamydia trachomatis, Treponema pallidum.