Long-term use of quinolones and their safety.

Although short courses of 4-quinolones are effective in routine infections, longer courses are necessary for chronic, deep-seated sepsis. Oral 4-quinolones exhibit efficacy equal to that of traditional parenteral regimens against osteomyelitis caused by gram-negative pathogens and have proved successful against chronic prostatitis and suppurative otorhinologic infections. The efficacy of these agents in the prophylaxis of urinary tract infection, travelers' diarrhea, and infections in neutropenic patients suggests other indications for potential widespread, long-term use. It is therefore important that the tolerability of regimens extending from 3-6 weeks to greater than or equal to 12 months has proved excellent. Potentially serious adverse reactions (including arthritis, cataract formation, and mutagenesis) noted in chronic animal toxicity or in vitro studies have no apparent human counterparts. However, experience is limited, and restrictions on use of the quinolones in children--except where real benefit outweighs theoretical risk--should not yet be abandoned.