Colistimethate sodium is used to treat pulmonary infections, especially in cystic fibrosis. The recommended adult dose is 1–2 million units (80–160 mg) nebulised colistimethate twice daily.
Colistimethate also known as polymyxin E, is an antibiotic produced by certain strains of the bacteria Paenibacillus polymyxa. Colistimethate is a mixture of the cyclic polypeptides Colistimethate A and B and belongs to the class of polypeptide antibiotics known as polymyxins.Colistimethate is effective against most Gram-negative bacilli.
Colistimethate is a decades-old drug that fell out of favor due to its nephrotoxicity. It remains one of the last-resort antibiotics for multidrug-resistant Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter. NDM-1 metallo-β-lactamase multidrug-resistant Enterobacteriaceae have also shown susceptibility to Colistimethate.