Due to a rapid increase in serious infections related to especially carbapenemase producing Enterobacterales, the clinical use of the polymyxin antibiotics colistin (polymyxin E), and polymyxin B has recently resurged as salvage therapy for otherwise untreatable Gram-negative infections.  Both polymyxins demonstrate rapid bactericidal killing against susceptible strains of Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii.

Polymyxin guidelines