Abstract
Objective: To provide a rationale for the increasing use of ofloxacin as a substitute for ciprofloxacin, and to review the appropriate use of these agents. Data Source: A MEDLINE search was conducted to identify relevant literature. References in those articles were reviewed for additional published information. Study Selection: Published review articles and clinical trials on ofloxacin were reviewed, with particular emphasis on pharmacoeconomics, pharmacodynamics, and studies evaluating the safety and efficacy of ofloxacin. Data Synthesis: Ofloxacin is a broad-spectrum antimicrobial agent that has in vitro activity similar to that of ciprofloxacin. Ciprofloxacin exhibits lower minimum inhibitory concentrations for Pseudomonas aeruginosa, and ofloxacin is more active against Chlamydia trachomatis and gram-positive aerobic organisms. Both agents have limited anaerobic activity. Unlike ciprofloxacin, ofloxacin is 100% bioavailable, exhibits a greater area under the concentration curve, contributing to its bactericidal activity, and is eliminated primarily by the kidney. Both ciprofloxacin and ofloxacin have long half-lives, allowing twice-daily dosing. However, because a decrease in renal function often accompanies increasing age, ofloxacin can be administered once daily in the elderly. Both agents have a large volume of distribution and exhibit excellent tissue and cell penetration. Several clinical studies have demonstrated ofloxacin's effectiveness in treating a variety of systemic infections caused by susceptible organisms, including P. aeruginosa. Adverse effects are infrequent with both fluoroquinolones, and if they occur such effects are usually gastrointestinal in nature. Ofloxacin has a much lower incidence of drug interactions, in particular with theophylline and caffeine. Ofloxacin is less expensive than ciprofloxacin. Conclusions: Overall, the activity of ofloxacin is similar to that of ciprofloxacin and the two agents are therapeutically equivalent. The data presented warrant routine therapeutic substitution of ofloxacin for ciprofloxacin. Ciprofloxacin should be reserved for instances in which specific prescribing criteria are met.