Treatment of Bacterial Conjunctivitis
The first-line treatment for bacterial conjunctivitis is a 5-7 day course of broad-spectrum topical antibiotic, with options including fluoroquinolones such as moxifloxacin 0.5% or gatifloxacin 0.5%. 1
Antibiotic Selection and Dosing
First-line Treatment Options:
Fluoroquinolones:
- Moxifloxacin 0.5% ophthalmic solution: Effective against common pathogens including S. aureus, S. epidermidis, S. pneumoniae, and H. influenzae 1
- Gatifloxacin 0.5% ophthalmic solution: Dosing for patients ≥1 year old 2:
- Day 1: One drop every two hours while awake (up to 8 times)
- Days 2-7: One drop 2-4 times daily while awake
Alternative antibiotics when appropriate:
- Gentamicin
- Tetracycline
- Ofloxacin 1
Special Cases:
- Gonococcal conjunctivitis: Requires systemic antibiotics plus topical therapy 1
- Chlamydial conjunctivitis: Requires systemic treatment 1
- Neonatal conjunctivitis: Immediate consultation required with treatment based on onset time 1:
- 1-7 days after birth: Consider gonococcal infection
- 5-19 days: Consider chlamydial infection
- First week: Common bacterial pathogens (S. aureus, Enterococcus, Klebsiella, E. coli)
Treatment Duration and Expected Outcomes
- Standard treatment duration: 5-7 days 1
- Clinical improvement typically occurs within 1-3 days of appropriate antibiotic treatment 1
- Patients can usually return to work or school after 24 hours of antibiotic treatment 1, 3
Delayed Antibiotic Prescribing
For mild cases of bacterial conjunctivitis, delayed antibiotic prescribing may be considered as it has shown similar symptom control compared to immediate prescribing 1, 3. This approach can help reduce unnecessary antibiotic use while maintaining treatment efficacy.
Prevention and Hygiene Measures
- Frequent handwashing
- Avoid sharing towels and pillowcases
- Proper contact lens care (patients should not wear contact lenses during treatment) 1, 2
- Strict personal hygiene to decrease transmission risk 3
Red Flags Requiring Ophthalmology Referral
Immediate referral is indicated for:
- Neonatal conjunctivitis
- Lack of response to therapy after 3-4 days
- Moderate to severe pain
- Decreased vision
- Corneal involvement
- Conjunctival scarring
- Recurrent episodes
- History of herpes simplex virus eye disease
- Immunocompromised patients 1
Common Treatment Pitfalls
- Overuse of antibiotics for viral conjunctivitis
- Prolonged use of corticosteroids without ophthalmology supervision
- Failure to recognize potentially serious causes of conjunctivitis
- Inadequate hygiene education
- Delayed referral for severe or non-responsive cases 1
Antibiotic Resistance Considerations
Increasing resistance to fluoroquinolones has been reported, particularly in methicillin-resistant Staphylococcus aureus (MRSA) isolates 4. A study of over 3,200 ocular isolates found methicillin resistance in 42% of Staphylococcal isolates, with high concurrent resistance to fluoroquinolones 4. This highlights the importance of considering local resistance patterns when selecting antibiotics.