What is the treatment for bacterial conjunctivitis?

Treatment of Bacterial Conjunctivitis

Bacterial conjunctivitis should be treated with a 5-7 day course of broad-spectrum topical antibiotic to accelerate clinical and microbiological remission, reduce transmissibility, and allow earlier return to school or work. 1, 2

First-Line Treatment Approach

• For mild bacterial conjunctivitis, apply a broad-spectrum topical antibiotic 4 times daily for 5-7 days 1, 2
• Moxifloxacin 0.5% ophthalmic solution is an effective option, administered as one drop in the affected eye 3 times a day for 7 days 3
• Azithromycin 1% ophthalmic solution can be used with a simpler regimen: 1 drop twice daily for the first two days, then once daily for five more days 4
• The most convenient or least expensive antibiotic option is appropriate as there is no clinical evidence suggesting superiority of any particular agent for uncomplicated cases 2

Treatment Based on Severity

Mild Bacterial Conjunctivitis

• Topical antibiotics reduce symptom duration and improve clinical outcomes even in mild cases 1
• By day 3-5 of treatment, 62% of patients receiving topical antibiotics show clinical cure compared to only 28% with placebo 5
• By day 8-10, bacterial eradication rates are significantly higher with antibiotics (79%) versus placebo (31%) 5

Moderate to Severe Bacterial Conjunctivitis

• Obtain conjunctival cultures and Gram staining before initiating treatment 1, 2
• More aggressive treatment approach is needed for cases with copious purulent discharge, pain, and marked inflammation 2
• Choice of antibiotic should be guided by laboratory test results when available 2

Special Pathogen Considerations

• For gonococcal conjunctivitis:

  • Requires systemic antibiotic therapy rather than topical treatment alone 1, 2
  • Saline lavage promotes comfort and faster resolution of inflammation 1
  • Daily follow-up until resolution is necessary 2

• For chlamydial conjunctivitis:

  • Requires systemic antibiotic therapy, especially in infants 1, 2
  • No evidence supports additional topical therapy beyond systemic treatment 1
  • Follow-up evaluation is important as treatment failure can occur in up to 19% of cases 2

• For MRSA infections:

  • Consider compounded topical antibiotics such as vancomycin 1, 2
  • Bacterial resistance is a growing concern with MRSA infections 1

Recommended Antibiotic Options

• Fluoroquinolones (e.g., moxifloxacin, gatifloxacin) are effective against common pathogens 1, 3
• Ciprofloxacin, chloramphenicol, and rifampin show good activity against the most prevalent pathogens (H. influenzae and S. pneumoniae) 6
• Polymyxin-bacitracin ophthalmic ointment has demonstrated efficacy in controlled trials 5
• Povidone-iodine 1.25% ophthalmic solution may be as effective as topical antibiotics and can be considered when access to antibiotics is limited 1, 2

Common Pathogens

• The most prevalent bacteria in bacterial conjunctivitis are Haemophilus influenzae (44.8%) and Streptococcus pneumoniae (30.6%) 6
• Other common pathogens include Staphylococcus aureus, Staphylococcus epidermidis, and Moraxella species 6, 7

Important Pitfalls and Caveats

• Return for follow-up if no improvement after 3-4 days of treatment 1
• Consider sexual abuse in children with gonococcal or chlamydial conjunctivitis 1, 2
• Patients should be advised not to wear contact lenses if they have signs or symptoms of bacterial conjunctivitis 3, 4
• Poor adherence to frequent administration regimens can contribute to treatment failure 1, 7
• Prolonged use may result in overgrowth of non-susceptible organisms, including fungi 3, 4
• Bacterial resistance is a growing concern that may be impacted by widespread antibiotic use and insufficient bactericidal concentrations at the infection site 7