MULTIPLE-DOSE PHARMACOKINETICS OF MOXISYLYTE AFTER ORAL-ADMINISTRATION TO HEALTHY-VOLUNTEERS

The pharmacokinetics of moxisylyte in plasma and urine was investigate d after oral administration. Twelve subjects were treated orally, twic e daily with 240 mg of the drug for 6 days; on day 7, the subjects rec eived a last dose of 240 mg of moxisylyte. Moxisylyte was assayed in p lasma and urine by a specific HPLC method with fluorimetric detection. Moxisylyte was absorbed rapidly and changed to its metabolites immedi ately after drug administration; unchanged moxisylyte was not found in plasma. Two metabolites were found in plasma and urine: conjugated de sacetylmoxisylyte (DAM) and the conjugate of desmethylated DAM (MDAM). The pharmacokinetic parameters determined after the first oral admini stration were not modified on multiple dosing. The apparent eliminatio n half-lives of conjugated DAM and MDAM were 2.3 and 3.5 h, respective ly. Elimination of these two metabolites in urine. averaged 50 and 1 0 %, respectively.