The pharmacoepidemiology and cost impact of ciprofloxacin use were evaluated after unrestricted availability in a 238-bed community teaching hospital. The medical records on all patients treated with oral ciprofloxacin over 6 months were reviewed. To determine if the availability of ciprofloxacin altered antibiotic usage patterns and outcome variables, a group of control patients from a period prior to ciprofloxacin availability were matched and compared to patients who had received the drug. Ciprofloxacin was used as both initial and replacement for parenteral therapy in a variety of infections. A successful clinical outcome was achieved in approximately 90% of patients treated with ciprofloxacin and resulted in an estimated cost avoidance of approximately $165/course. However, comparisons with the matched-control group revealed no differences in overall antibiotic costs or length of hospital stay. These results suggest that unrestricted availability of oral ciprofloxacin does not ensure changes in outcome variables related to cost. Educational and patient targeting programs may be necessary to promote earlier conversion of appropriate patients to newer oral therapies.