Objective: To assess the safety and tolerability of bolus intravenous doses of colistin during acute respiratory exacerbations in adults with cystic fibrosis and chronic Pseudomonas aeruginosa infection.
Methods: Twelve patients with acute exacerbations of cystic fibrosis were enrolled in a Phase I open-label study. On day 1, patients received three doses of colistin 2 mega-units (160 mg), reconstituted in 50 mL of NaCl 0.9%, by infusion over 30 minutes three times daily. On days 2, 3, and 4, the same dose of colistin was administered by bolus injection three times a day over five minutes after reconstitution in 20, 15, and 10 mL of NaCl 0.9%, respectively. The injection was given by a nurse or physician using a hand-held syringe. If the latter dose was tolerated, it was continued for the remaining eight days of the study. If any dose was not tolerated, treatment reverted to the previously tolerated concentration, which was continued throughout the remainder of the study.
Results: No serious adverse events occurred during the course of the trial. Patients without total indwelling venous access systems experienced mild to moderate injection pain. There were no clinically significant changes in renal function.
Conclusions: This study indicates that the administration of bolus intravenous colistin as 2 mega-units (160 mg) in 10 mL of NaCl 0.9% three times a day is safe. It is well-tolerated by patients with total indwelling venous access systems.