A study to determine the pharmacokinetics and inflammatory fluid penetration of gatifloxacin following a single oral dose.

A single 400 mg oral dose of gatifloxacin was given to each of nine healthy male volunteers and the concentrations of the drug in plasma, cantharidine-induced inflammatory fluid and urine were measured over the following 24 h. The mean peak concentration in plasma of 4. 1 mg/L was attained at a mean time of 1.8 h post dose. The mean peak concentration in inflammatory fluid was 3.6 mg/L and was attained at a mean time of 4.2 h post dose. The mean plasma elimination half-life of gatifloxacin was 6.8 h and that in inflammatory fluid was 7.2 h. The mean penetration into the inflammatory fluid was 117%. Recovery of drug from urine during the first 24 h post dose was 65% of that administered. Our data suggest that gatifloxacin dosed at 400 mg od should be adequate to treat systemic infections caused by most bacterial species.