The selection of appropriate dosages for intravenous ciprofloxacin.

A variety of toxicological, clinical and pharmacokinetic parameters were utilized in an evolving process to determine the optimum dosage for intravenous ciprofloxacin. Despite the clinical efficacy of 200-300 mg administered every 12 h, there have been concerns that this might be inadequate for certain pathogens, including Pseudomonas aeruginosa, Staphylococcus aureus and streptococci. Pharmacokinetic studies have established the bioequivalence of the iv and oral formulations of ciprofloxacin. With respect to the AUC, 400 mg of iv ciprofloxacin was equivalent to 500 mg po and the Cmax of 400 mg administered iv over 1 h approximated that following a 750 mg tablet. Final FDA approval of iv ciprofloxacin was ultimately based on the demonstration of the bioequivalence of the iv and oral formulations, the latter having proven clinical efficacy. For severe systemic infections, a daily dosage of 1200 mg (400 mg tds) of iv ciprofloxacin would be equivalent to 1500 mg (750 mg bd) taken by mouth.