everal new quinolones have been developed and used as effective antibacterial agents to treat a variety of infections

It was reported that new quinolones might inhibit the activities of hepatic microsomal enzymes.Inthis report

the effects of enoxacin and norfloxacin on rat hepatic microsomal cytochrome P 450 were investi-gated.Hypnotic time induced by sodium pentobarbital was significantly prolonged in rats with enoxacin(200mg/kg

qd × 7d)

while it was only slightly prolonged with norfloxacin. Enoxacin(200mg/kg

qd×7d)markedy in-hibited liver microsomal cytochrome P--450

but norfloxacin did so slightly. The results strongly suggest thatenoxacin markedly and norfloxacin slightly inhibited the activities of cytochrome P-450 in liver microsomes.