Abstract
Antibacterial activities of a newly synthesized quinolone antimicrobial drug, balofloxacin, against four species of Streptococcus in the oral cavity showed minimum 90% inhibitory concentrations (MIC90) ranging from 0.39 to 0.78 μg/ml, which were approximately equal to that of the control drug, tosufloxacin, and stronger than those of ofloxacin and ciprofloxacin by 2-4 times.
When the drug was administered at a dose of 200 mg to seven healthy adult fasting volunteers, the maximum blood concentration rose to 1.35±0.12μg/ml 1.7 hours after administration. The time when the concentration was at a maximum (Tmax) was slightly prolonged by postprandial administration, but the blood maximum concentration (Cmax) and the area under the curve (AUC) were nearly unchanged after administration. The salivary concentration showed changes generally resembling those of the serum concentration, and the salivary to serum blood concentration ratio was 50-90%.
When the concentration in blood retained at the wound immediately after extraction, with the drug being administered at a dose of 100 mg (to 29 subjects) or 200 mg (to 44 subjects) to subjects who were to undergo extraction, the 100 mg dose group showed a distribution from 0-1.66μg/ml 1.75-4.5 hours after administration, while the 200 mg dose group showed this distribution from 0.5 to 4.25 hours after administration, suggesting that wound concentrations essentially correspond to the blood concentrations.
