Polymyxin B and Trimethoprim Ophthalmic Solution

Generic name: polymyxin b sulfate and trimethoprim sulfate
Dosage form: ophthalmic solution
Drug class:Ophthalmic anti-infectives

Medically reviewed by Drugs.com. Last updated on Oct 22, 2021.

(Sterile)

Rx only

FOR TOPICAL APPLICATION IN THE EYE

*Does not meet USP packaging specification for light resistance.

Polymyxin B and Trimethoprim Ophthalmic Solution Description

Polymyxin B Sulfate and Trimethoprim Ophthalmic Solution, USP* is a sterile antimicrobial solution for topical ophthalmic use. It has a pH of 4.0 to 6.2 and osmolality of 270 to 310 mOsm/kg.

Chemical Names: Trimethoprim sulfate, 2,4-diamino-5-(3,4 5-trimethoxybenzyl)pyrimidine sulfate (2:1), is a white, odorless, crystalline powder with a molecular weight of 678.72 and the following structural formula:

C28H38N8O10S
Mol. Wt. 678.72

Polymyxin B sulfate is the sulfate salt of polymyxin B1 and B2 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 – 6.2). PRESERVATIVE ADDED: Benzalkonium Chloride 0.004%.

Polymyxin B and Trimethoprim Ophthalmic Solution - Clinical Pharmacology

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 bindin..