An international study shows that critical illness does not alter levofloxacin pharmacokinetics
Levofloxacin is a widely used antibiotic with a broad spectrum of activity against Gram-positive, Gram-negative, and atypical pathogens. It is commonly used to treat critically ill patients and data suggest the non-standard dosing regimens should be used. The aim of this study was to compare the population pharmacokinetics in both critically ill and non-critically ill patients. The study was carried out by an international group of researchers at the University of Queensland, Brisbane, Australia, the Pharmacy Department, Royal Brisbane and Womens’ Hospital, Brisbane, and a series of departments at the University of Udine, Italy.
Both critically ill patients and non-critically ill patients were included who were 18 years of age or over with a serum creatinine <1.5 g/dl. The study protocol involved administration of 500mg or 750mg levofloxacin 24-hourly as an iv infusion given over a period of 60 minutes. Plasma was obtained from blood samples collected on Day 1 and Day 2. Plasma levofloxacin concentrations were measured by HPLC-UV and data were fitted to one and two-compartment models using the Nonparametric Adaptive Grid (NPAG) algorithm. The study involved 35 patients, 18 of whom were critically ill.
Detailed analysis of the results showed that the data were best described by a two-compartment model and the presence of a critical illness did not significantly affect any of the pharmacokinetic parameters and creatinine clearance was the only covariate that affected levofloxacin clearance. The authors propose larger studies to investigate the effect of additional variables like the infection site and fluid status.
Antimicrob Agent Chemother. 2015 Dec 14. pii: AAC.02610-15. [Epub ahead of print]
Source : http://www.ncbi.nlm.nih.gov/pubmed/26666946?dopt=Abstract