培氟沙星（ＰＦＸ）为一种新型氟喹诺酮类抗生素。用微生物法测定６例患者在口服小剂量ＰＦＸ（每次２００ｍｇ，每日两次）稳态血和尿药浓度，显示较ＰＦＸ对肠道和泌尿道常见致病菌最低抑菌浓度（ＭＩＣ）高１０至数十倍。另外还对口服小剂量ＰＦＸ治疗的１０５例轻、中度泌尿道和肠道感染患者的疗效进行了评价，有效率为９７．１％，痊愈率为８８．６％，不良反应发生率低，程度轻。 Pefloxacin (PFX) is a novel fluoroquinolone antibiotic. Microecological method was used to determine the steady-state blood and urinary drug concentrations in 6 patients under oral low-dose PFX (200mg twice daily), which showed that the MICs were lower than those of PFX on common pathogenic bacteria in gut and urinary tract, 10 to 10 times higher. In addition, 105 patients with mild to moderate urinary tract and intestinal infections treated with low-dose oral PFX were also evaluated. The effective rate was 97.1%, the cure rate was 88.6%, the incidence of adverse reactions was low, Light degree.