polymyxin b sulfate

Polymyxin B Sulfate (Poly-RX) is a mixture of polymyxins B1 and B2, obtained from Bacillus polymyxa strains. They are basic polypeptides of about eight amino acids and have cationic detergent action on cell membranes. Polymyxin B Sulfate (Poly-RX) is used for infections with gram-negative organisms, but may be neurotoxic and nephrotoxic.

Polymyxin B2, a significant component of polymyxin B, is an antibiotic cationic lipopeptide initially derived from B. polymyxa. This compound effectively inhibits P. aeruginosa, A. baumannii, K. pneumoniae, and E. cloacae strains, exhibiting minimum inhibitory concentrations (MICs) of 1-2, 0.5-1, 0.25-0.5, and 0.25-1 µg/ml, respectively. Notably, in a mouse model of P. aeruginosa bloodstream infection, administration of polymyxin B2 at a dosage of 4 mg/kg has been shown to decrease the number of colony-forming units (CFUs) in the blood.