What is the treatment for bacterial conjunctivitis?

Treatment of Bacterial Conjunctivitis

Topical antibiotics are recommended for bacterial conjunctivitis as they reduce symptom duration and improve clinical outcomes, even in mild cases. 1

Treatment Based on Severity

Mild to Moderate Bacterial Conjunctivitis

• A 5-7 day course of broad-spectrum topical antibiotic is recommended as it accelerates clinical and microbiological remission, reduces transmissibility, and allows earlier return to school/work 1
• Fluoroquinolones (e.g., gatifloxacin, moxifloxacin) are effective against common pathogens including Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Haemophilus influenzae 2
• Povidone-iodine 1.25% ophthalmic solution may be as effective as topical antibiotics and can be considered when access to antibiotics is limited 3
• Patients should be advised to return for follow-up if no improvement is seen after 3-4 days of treatment 3

Moderate to Severe Bacterial Conjunctivitis

• Characterized by copious purulent discharge, pain, and marked inflammation 3
• Obtain conjunctival cultures and Gram staining before initiating treatment, especially if gonococcal infection is suspected 3, 1
• Choice of antibiotic should be guided by laboratory test results 3
• Consider methicillin-resistant S. aureus (MRSA) as a potential pathogen, which may require specialized antibiotics such as vancomycin 3

Special Cases

Gonococcal Conjunctivitis

• Requires systemic antibiotic therapy rather than topical treatment alone 3, 1
• Saline lavage may promote comfort and more rapid resolution of inflammation 3
• If corneal involvement is present, add topical treatment as for bacterial keratitis 3
• Patients should be seen daily until resolution 3
• Screen for concomitant sexually transmitted infections and treat sexual contacts 3, 1

Chlamydial Conjunctivitis

• Requires systemic antibiotic therapy, especially in infants who may have infection at other sites 3, 1
• No evidence supports additional topical therapy beyond systemic treatment 1
• For neonates with chlamydial conjunctivitis, oral erythromycin is recommended 1
• Treatment failure can occur in up to 19% of cases, requiring re-evaluation 3
• Sexual contacts should be treated concurrently 3

Antibiotic Selection

• Gatifloxacin 0.5% ophthalmic solution: Instill one drop every two hours while awake (up to 8 times) on Day 1, then 2-4 times daily on Days 2-7 2
• Effective against common pathogens including Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Haemophilus influenzae 2
• Other effective options include ciprofloxacin, chloramphenicol, and rifampin 4
• Besifloxacin 0.6% ophthalmic suspension has shown high potency against common ocular pathogens, including bacteria resistant to other fluoroquinolones 5

Pitfalls and Caveats

• Bacterial resistance is a growing concern, particularly with MRSA infections 3, 6
• Poor adherence to frequent administration regimens can contribute to treatment failure 1
• Contact lens wear should be discontinued during treatment 2
• Consider sexual abuse in children with gonococcal or chlamydial conjunctivitis 3, 1
• Most cases of bacterial conjunctivitis are self-limiting, but treatment shortens duration and reduces contagion 7
• Increasing resistance to fluoroquinolones has been reported, particularly in Staphylococcal species 6
• Methicillin-resistant S. aureus may require specialized antibiotics as they are often resistant to commercially available topical antibiotics 3