Polymyxin B Sulfate And Trimethoprim Sulfate

DESCRIPTION Polymyxin B sulfate and trimethoprim ophthalmic solution, USP is a sterile antimicrobial solution for topical ophthalmic use. It has pH of 4.0 to 5.5 and osmolality of 270 to 310 mOsm/kg. Chemical Names: Trimethoprim sulfate, 2,4-diamino-5-(3,4,5-trimethoxybenzyl) pyrimidine sulfate, is a white, odorless, crystalline powder with a molecular weight of 678.72 and the following structural formula: C 28 H 38 N 8 O 10 S Mol. Wt. 678.72 Polymyxin B sulfate is the sulfate salt of polymyxin B 1 and B 2 which are produced by the growth of Bacillus polymyxa (Prazmowski) Migula (Fam. Bacillaceae). It has a potency of not less than 6,000 polymyxin B units per mg, calculated on an anhydrous basis. The structural formula is: Each mL contains: Actives: polymyxin B sulfate equal to 10,000 polymyxin B units, trimethoprim sulfate (equivalent to trimethoprim 1 mg); Inactives: purified water, sodium chloride. Sulfuric acid and, if necessary, sodium hydroxide may be added to adjust pH (4.0 – 5.5). Preservative: benzalkonium chloride 0.004% Trimethoprim sulfate (Structural formula) Polymyxin B Sulfate, the sulfate salt of polymyxin B1 and B2 (Structural formula)