Quality of use of parenteral metronidazole therapy in a teaching hospital.

The recent release, relatively high cost and potential adverse effects of parenterally administered metronidazole prompted a quality-of-use audit at a 1000-bed teaching hospital. Ninety-two courses of treatment in 81 inpatients during a 6-week period were studied. Appropriateness of therapy was assessed on the basis of published indications. Parenterally administered metronidazole was prescribed primarily in anaerobic and anaerobic-aerobic infections. It was used as frequently for prophylaxis as for therapy. Surgical services accounted for 95% of the treatment courses. Inappropriate use was noted in 27 (29%) of the courses: agents other than parenterally administered metronidazole were indicated in 12 (13%), while the dose, dosing interval or duration of treatment was suboptimal in 15 (16%). Substantial savings would be achieved if oral or rectal metronidazole therapy were substituted for intravenous therapy for perioperative prophylaxis in elective colorectal surgery. Written justification for use and automatic stop orders are recommended to improve the cost effectiveness of both prophylactic and therapeutic use of selected antimicrobial agents.