Overview
Erythromycin is a macrolide antibiotic used primarily for bacterial infections. This specific formulation is an ophthalmic ointment indicated for superficial eye infections and neonatal ophthalmia prophylaxis. It works by inhibiting bacterial protein synthesis.
Mechanism of Action
Erythromycin binds to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis by blocking transpeptidation and translocation steps. This bacteriostatic action prevents bacterial growth and replication.
Indications
- Treatment of superficial ocular infections involving conjunctiva and/or cornea caused by susceptible organisms
- Prophylaxis of ophthalmia neonatorum due to Neisseria gonorrhoeae or Chlamydia trachomatis
Common Doses
- Ophthalmic ointment 0.5%
Dosage
For ocular infections: Apply approximately 1 cm ribbon directly to infected eye(s) up to 6 times daily based on severity. For neonatal prophylaxis: Instill approximately 1 cm ribbon into each lower conjunctival sac; do not flush from eye. Use new tube for each infant.
Contraindications
- History of hypersensitivity to erythromycin
Side Effects
- Minor ocular irritation
- Redness
- Hypersensitivity reactions
Interactions
- May potentiate effects of drugs metabolized by CYP3A4 (e.g., warfarin, carbamazepine, theophylline)
- Concurrent use with CYP3A4 inhibitors may increase erythromycin toxicity
Counseling Points
- Wash hands before and after application
- Do not touch tube tip to any surface to avoid contamination
- Complete full course even if symptoms improve
- Contact healthcare provider if irritation worsens or persists
- For neonates: Use new tube for each infant