FDA notified healthcare professionals and cystic fibrosis patients in U.S that the Agency is investigating the possible connection between the use of a liquid solution of Colistimethate that was premixed for inhalation with a nebulizer and the death of a patient with cystic fibrosis (CF).

Colistimethate is FDA approved for intravenous or intramuscular injection for the treatment of acute or chronic infections due to sensitive strains of certain Gram-negative bacilli, particularly sensitive strains of Pseudomonas aeruginosa which are a significant problem for patients with CF and for patients with neutropenia, and/or immune system compromise. The product is not FDA approved for use as a liquid to be inhaled via nebulizer. In this case, the drug was prepared by a pharmacy and dispensed as prescribed in premixed unit dose ready-to-use vials. Once Colistimethate is mixed into a liquid form, the product breaks down into other chemicals that can damage lung tissue.

Healthcare professionals who choose to prescribe Colistimethate to treat patients with CF should be aware of the potential for serious and life threatening side effects from inhalation of pre-mixed, ready-to-use liquid forms of the product. Patients should discard
.any unused pre-mixed liquid forms of Colistimethate