The pharmacokinetics of lomefloxacin tablet and capsule were determined following a single oral dose of 400 mg given to each of 10 Chinese healthy male volunteers in an open, randomized crossover study. Drug concentrations in plasma were assayed by HPLC method. The peak levels in plasma averaged 6.0 +/- 1.3 and 5.9 +/- 1.0 micrograms.ml-1 at 1.3 +/- 0.4 and 1.2 +/- 0.4 h, and the areas under the drug concentration curves were 43 +/- 15 and 44 +/- 13 h.micrograms.ml-1 for lomefloxacin tablet and capsule, respectively. The concentration-time courses after medication conformed to a 1-compartment open model with a first order absorption. Pharmacokinetic parameters after tablet did not differ significantly from the corresponding values after capsule. The bioavailability of tablet was comparable to that of capsule.