Disposition kinetics of ethyl biscoumacetate and its metabolite 7-hydroxy ethyl biscoumacetate were evaluated in ten healthy volunteers, after a single 300 mg oral dose of ethyl biscoumacetate. Serum concentrations of parent compound and its metabolite were measured by HPLC. The maximum serum ethyl biscoumacetate concentrations were reached 1.0-4.0 hours after drug dosing. From 3 hours after drug administration the concentration of the metabolite was always higher than the concentration of the parent compound. Geometric mean of elimination half-life was 0.66 hours for ethyl biscoumacetate and 2.03 hours for the 7-hydroxy ethyl metabolite.