-2%
Erosa (Erythromycin)|Therapeutic Class: Anti-diarrhoeal Antimicrobial, Macrolide Antibiotic
Erosa (Erythromycin) belongs to the macrolide group of antibiotics. It acts by interfering with bacterial ribosomal protein synthesis, exerting either a bacteriostatic or bactericidal effect depending on concentration and organism susceptibility.
- Erosa is particularly effective against penicillinase-producing staphylococci, making it a valuable alternative for patients allergic to penicillin.
- Susceptible organisms include:
- Gram-positive: Cocci and bacilli
- Gram-negative: Neisseria catarrhalis, N. meningitidis, N. gonorrhoeae, Haemophilus influenzae, Bordetella pertussis
- Other microorganisms: Mycoplasma pneumoniae, Legionella pneumophila, Bacteroides fragilis, B. oralis, B. melaninogenicus, Fusobacterium, Chlamydia trachomatis, Treponema pallidum
Erythromycin inhibits bacterial protein synthesis by binding to the 50S subunit of the ribosome, preventing translocation during translation. It does not bind to mammalian ribosomes (80S), ensuring selective antibacterial activity.
- Absorption:
The base form is acid-labile and is administered as acid-stable esters (e.g., stearate). Food reduces absorption. - Distribution:
Widely distributed in body tissues and fluids, with higher concentrations in the liver and spleen. Protein binding is approximately 73%. It crosses the placenta and is excreted in breast milk. - Metabolism and Excretion:
About 5–15% of the dose is excreted unchanged in urine; the majority is excreted in bile. - Half-life:
Approximately 1.2–4 hours (prolonged to 5 hours in renal impairment).