The new quinolones: back to the future.

Few agents developed for the treatment of infectious diseases have been heralded to the same extent as the new quinolone derivatives. While these compounds are extremely promising, we still have much to learn about their biologic properties. Detailed analyses of, for example, the mode of action at the target level could have implications for the study and design of both prokaryotic and eukaryotic topoisomerase inhibitors. It is significant that, in spite of the fact that these potent new antimicrobial agents have been in use for only a few years, resistant strains have appeared and have begun to affect the therapeutic potential of the quinolones. Prudent use of these agents will be an important measure of guaranteeing their maximal benefit in future clinical practice.