Fluoroquinolone antibiotics: properties of the class and individual agents

The broad spectrum of activity and bactericidal nature of the fluoroquinolones, together with their excellent absorption, rapid distribution, and high tissue concentration, make them excellent therapeutic agents for the management of a number of complicated community-acquired and nosocomial infections of the urinary tract, bone and soft tissue, gastrointestinal tract, and prostate, as well as some respiratory tract infections and sexually transmitted diseases. Data are presented and reviewed concerning the in vitro activity, pharmacology, and clinical use of ciprofloxacin, norfloxacin, and ofloxacin, which have been available for some time, and lomefloxacin and temafloxacin, which are recently approved agents. The comparable qualities and differences in activity and clinical applications of these agents are considered. For many infections in selected patients, quinolones are excellent substitutes for parenteral agents. In general, adverse effects have been infrequent and rarely require drug discontinuation. Significant interactions, such as with theophylline and caffeine, have occurred but are quinolone dependent. Antacids can markedly impair the absorption of all quinolones. Because emerging resistance to Pseudomonas and Staphylococcus species have been observed, the improper use of the quinolones must be avoided, and the clinician must be aware that an unfavorable response may signal resistance. The development of future agents with better gram-positive activity, improved gram-negative coverage, and activity against unusual pathogens such as Chlamydia species and Mycobacterium species, will make these oral agents invaluable. Assessing the usefulness and safety of these antibiotics in children is an ongoing challenge.