抄録
Fleroxacin (FLRX), a new synthetic quinolone antimicrobial, was developed by chemically modifying norfloxacin (NFLX) . It is easily absorbed, passed and long-acting. However, the absorption of new quinolones is reportedly suppressed by metal cations contained in antacids. The degree of suppression varies with the drug : it is generally greater with NFLX, and less with FLRX.
When antimicrobials are prescribed by dentists for patients with weak stomach, antacids are frequently used in combination. The effect on the migration of FLRX and NFLX of a dispensing stomachic Sankyo Magen Mittel (S·M powder®), containing about 30% aluminum magnesium silicate, was studied.
FLRX (200mg) and S·M powder® (1.3g), were simultaneously administered to seven normal adults and blood was collected at specified intervals. FLRX, (20mg/kg), and S·M powder®, (26mg/kg), were administered to male New Zealand white rabbits to collect blood and oral tissues. Concentration was measured by the thin layer disc method using Escherichia coli NIHJ JC2, and results obtained were analyzed pharmacokinetically. The passage of NFLX into rabbit sera was also evaluated.
1) S·M powder® reduced the transfer of FLRX (200mg) into human sera with prolonged Tmax of 0.44hr., and decreased Cmax by about 19%.
2) S·M powder® reduced the passage of FLRX (20mg/kg) into rabbit sera, with prolonged Tmax of 0.39hr., and reduced Cmax by about 8.4%. Tmax in the rabbit oral cavity tissues was similar to that in the bones, but was prolonged from 7.3% to 30.8% in every tissue.
3) As 20mg/kg of NFLX administered to rabbits revealed no detectable serum level, 50mg/kg was administered. As a result, Tmax was prolonged 0.21hr., and Cmax decreased about 42% in the group treated with S·M powder®.
4) FLRX passed more satisfactorily than NFLX, although it was inhibited by S·M powder® to a lesser degree.
