Fluoroquinolone adverse effects and drug interactions

Extensive pharmacologic and clinical development of quinolone antimicrobial agents has resulted in improved antimicrobial activity, pharmacokinetic fe atures, toxicity, and drug-drug interaction profiles. Nalidixic acid and ot her early quinolones had limited use due to poor pharmacokine tics, relativ ely narrow antimicrobial spectrum of activity, and frequent adverse effects . Be-ginning with the development of fluoroquinolones, such as norfloxacin and ciprofloxacin, in the 1980s, the agents assumed a greatly expanded clin ical role because of their broad antimicrobial spectrum of action, improved pharmacokinetic properties, and more acceptable safety profile. Although t he pharmaco kinetics and efficacy of the drugs have improved significantly, a major area of continued emphasis is to further reduce the frequency and severity of adverse events and drug-drug interactions. Older agents such as ciprofloxacin and ofloxacin are still extensively prescribed, but the focu s of this article is on the newer fluoroquinolones (levofloxacin and other drugs that have been approved or have been under investigation since approx imately 1997).