Lack of interaction between levofloxacin and oxycodone: Pharmacokinetics and drug disposition

Previous studies have demonstrated a significant reduction in the oral bioa vailability of trovafloxacin and ciprofloxacin when administered concomitan tly with an intravenous opiate such as morphine. This decrease in absorptio n results in a 36% and 50% lower AUC for trovafloxacin and ciprofloxacin, r espectively, which could cause clinical failures. The authors investigated the possibility of a similar interaction between oxycodone and levofloxacin . Eight healthy volunteers were randomized in an open-label, two-way cross- over study to receive oxycodone, 5 mg po Q4H, and levofloxacin, 500 mg po 1 hour after starting the oxycodone or levofloxacin 500 mg po alone. Blood s amples were drawn at 0, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 18, and 24 hours fo r C-max, t(max), and AUC determinations. There was not a significant differ ence (p > 0.05) in AUC(48.59 +/- 8.52 vs. 49.9 +/- 9.93), C-max (7.73 +/- 2 .6 vs. 6.6 +/- 2.0), and t(max) (1.1 +/- 0.6 vs. 1.6 +/- 1.1) for levofloxa cin versus levofloxacin/oxycodone regimens. If was concluded that oral oxyc odone and levofloxacin can be administered concomitantly without a signific ant decrease in AUC, C-max or t(max). (C) 2001 the American College of Clin ical Pharmacology.