Polymyxin B Trimethoprim Ophthalmic Solution for Bacterial Conjunctivitis
For bacterial conjunctivitis, instill one drop of polymyxin B trimethoprim ophthalmic solution in the affected eye(s) every three hours (maximum of 6 doses per day) for 7-10 days. 1
Dosage Regimen
- For adults and children over 2 months of age with mild to moderate bacterial conjunctivitis, the recommended dosage is one drop in the affected eye(s) every three hours, not exceeding 6 doses per day 1
- The typical treatment duration is 7-10 days to ensure complete resolution of infection 1
- Clinical studies have confirmed this dosage regimen is safe and effective for pediatric patients over two months of age 1
Efficacy and Clinical Outcomes
- Topical antibiotics like polymyxin B trimethoprim reduce symptom duration and improve clinical outcomes in bacterial conjunctivitis 2
- In clinical studies, 95% of infected eyes treated with trimethoprim-polymyxin B were cured or improved within 7 days 3
- Physicians have rated the overall efficacy of trimethoprim-polymyxin B as excellent or good in 96% of cases 3
Comparative Efficacy
- While polymyxin B trimethoprim is effective, studies show that newer fluoroquinolones like moxifloxacin may work faster, with 81% of patients showing complete resolution at 48 hours compared to 44% with polymyxin B trimethoprim 4
- Clinical response rates at treatment completion are similar between trimethoprim-polymyxin B, gentamicin sulfate, and sodium sulfacetamide (84%, 88%, and 89% cure rates respectively) 5
Patient Comfort and Tolerability
- Patients or caregivers report that treatment with polymyxin B trimethoprim is very comfortable or moderately comfortable in 89% of cases 3
- Adverse events are rare, typically transient and of mild-to-moderate intensity 3
Special Considerations
- For more severe bacterial conjunctivitis (large infiltrates or hypopyon), consider obtaining conjunctival cultures before initiating treatment 2
- Bacterial resistance is a growing concern, particularly with MRSA infections; consider alternative treatments if no improvement after 3-4 days 2
- For gonococcal or chlamydial conjunctivitis, polymyxin B trimethoprim alone is insufficient; systemic antibiotics are required 2, 6
Treatment Algorithm
- Confirm diagnosis of bacterial conjunctivitis
- For mild to moderate cases: Begin polymyxin B trimethoprim ophthalmic solution (1 drop every 3 hours, maximum 6 doses daily) 1
- Continue treatment for 7-10 days even if symptoms improve earlier 1
- If no improvement after 3-4 days, consider obtaining cultures and changing antibiotic therapy 2
- For severe cases or special populations (gonococcal, chlamydial), consider alternative or additional systemic therapy 2, 6