Polytrim Generic Name & Formulations
Trimethoprim (as sulfate) 1 mg, polymyxin B sulfate 10000 Units/mL; oph. soln; contains benzalkonium chloride.
Folic acid inhibitor + antibiotic.
Mechanism of Action
Trimethoprim is a synthetic antibacterial drug active against a wide variety of aerobic gram-positive and gram-negative ophthalmic pathogens. Trimethoprim blocks the production of tetrahydrofolic acid from dihydrofolic acid by binding to and reversibly inhibiting the enzyme dihydrofolate reductase. This binding is stronger for the bacterial enzyme than for the corresponding mammalian enzyme and therefore selectively interferes with bacterial biosynthesis of nucleic acids and proteins. Polymyxin B, a cyclic lipopeptide antibiotic, is bactericidal for a variety of gram-negative organisms, especially Pseudomonas aeruginosa. It increases the permeability of the bacterial cell membrane by interacting with the phospholipid components of the membrane.
Susceptible surface ocular bacterial infections.
Polytrim Dosage and Administration
Adults and Children
<2 months: not recommended. ≥2 months: 1 drop every 3 hours for 7–10 days; max 6 doses/day.
Polytrim Boxed Warnings
Discontinue if sensitivity or superinfection occurs. Pregnancy (Cat.C). Nursing mothers.
Polytrim Adverse Reactions
Local irritation or discomfort, superinfection.
Polytrim Clinical Trials
Polytrim Patient Counseling