Pharmacokinetics of ciprofloxacin in healthy volunteers and patients with impaired kidney function.

The pharmacokinetics of ciprofloxacin were studied, in six healthy controls and in 18 patients with varying degrees of renal impairment, after administration of a single 100 mg intravenous dose. Pharmacokinetic parameters were calculated on a two compartment open model. The mean distribution volume was 2.1 (+/- 0.6) l/kg of ideal body weight; it did not correlate significantly with renal function. In the healthy volunteers 57 (+/- 9)% of the drug was eliminated by the kidney and 43% by other pathways. The renal clearance of ciprofloxacin correlated with creatinine clearance (rs = 0.93, P less than 0.001), and urinary excretion of the drug was markedly reduced in patients with the most severe degrees of renal impairment. Plasma clearance correlated with creatinine clearance (rs = 0.50, P less than 0.02). This together with the lack of correlation between non-renal clearance and renal function enables us to suggest an intravenous dosage schedule for patients with renal impairment.