Erythromycin for Bacterial Conjunctivitis
Erythromycin ophthalmic ointment is effective for bacterial conjunctivitis and should be applied directly to the infected eye(s) up to six times daily, depending on the severity of the infection. 1
Indications and Efficacy
Erythromycin ophthalmic ointment is indicated for:
- Treatment of superficial ocular infections involving the conjunctiva and/or cornea caused by susceptible organisms 1
- Prophylaxis of ophthalmia neonatorum due to N. gonorrhoeae or C. trachomatis 1
Studies show that topical antibiotics like erythromycin are beneficial in:
- Speeding clinical remission (36% faster in days 2-5) 2
- Improving microbiological cure rates (55% higher in days 2-5) 2
- Allowing earlier return to school or work 3
Dosage and Administration
For bacterial conjunctivitis:
- Apply approximately 1 cm of erythromycin ophthalmic ointment directly to the infected eye(s)
- Use up to six times daily, depending on infection severity 1
- Continue treatment for 5-7 days as recommended for topical antibiotics 4
For neonatal prophylaxis:
- Apply a 1 cm ribbon of ointment into each lower conjunctival sac
- Do not flush the ointment from the eye after instillation
- Use a new tube for each infant 1
Clinical Considerations
When to Use Antibiotics
While bacterial conjunctivitis can be self-limiting (41% resolve without antibiotics by days 6-10) 2, treatment is recommended to:
- Speed symptom resolution
- Reduce infection duration
- Decrease risk of complications and transmission 4
Recognizing Bacterial Conjunctivitis
Key distinguishing features include:
- Purulent or mucopurulent discharge
- Matting of eyelids (especially upon waking)
- Conjunctival injection
- Mild discomfort or foreign body sensation
- Absence of significant pain or vision loss 4
Common causative organisms include:
- Haemophilus influenzae
- Streptococcus pneumoniae
- Staphylococcus aureus
- Moraxella species 4
Supportive Measures
In addition to antibiotic therapy, recommend:
- Warm compresses (preferred over cold for bacterial conjunctivitis) to soften discharge and loosen crusts 4
- Proper hygiene measures including frequent handwashing, separate towels, and avoiding sharing pillowcases 4
- For contact lens wearers: discontinue lens wear until infection resolves 4
When to Refer to an Ophthalmologist
Refer patients with:
- No response to therapy after 3-4 days
- Visual loss
- Moderate or severe pain
- Severe purulent discharge
- Corneal involvement
- Conjunctival scarring
- Recurrent episodes
- History of herpes simplex virus eye disease
- Immunocompromised status 4
Special Considerations
- For gonococcal or chlamydial conjunctivitis, systemic therapy is required in addition to topical treatment 4, 3
- Neonatal conjunctivitis requires immediate referral as it may indicate serious infections 4
- Consider local resistance patterns when selecting antibiotics, as increasing resistance to some antibiotics has been reported 4
Pitfalls to Avoid
- Using antibiotics for viral conjunctivitis, which will not respond to antibacterial agents 4
- Failing to recognize more serious conditions that may mimic conjunctivitis
- Inadequate duration of treatment, which may lead to recurrence
- Not addressing contact lens wear, which can be a risk factor for certain infections 4