Dosing adjustment of 10 antimicrobials for patients with renal impairment

Abstract

OBJECTIVE: To describe a program of creatinine clearance-based dosage adjustment of 10 renally eliminated antimicrobial agents and to discuss the utility of such a program in a hospital as a method of quality assurance (by ensuring that patients with renal impairment receive generally accepted dosage adjustments), based on pharmacodynamic principles. METHODS: Consecutive patients prescribed any of 10 targeted renally eliminated antibiotics were included. Recommendations for dosage adjustment were made to the prescribe based on a calculated creatinine clearance. Additional adjustments in drug therapy were performed, including dosage recommendations of nontargeted drugs, simplification of antibiotic regimens, and conversion of intravenous to oral therapy. A cost analysis was performed. RESULTS: During a 6-month study period, 160 dosage changes (7.6% of total number screened) were recommended in 137 patients receiving the targeted antimicrobial agents. Prescribes accepted 147 recommendations (91.9%). A dosage change recommendation was necessary more than 12% of the time of acyclovir, ceftazidime, and imipenem/cilastatin. A cost avoidance of $11 702.08 was realized. Ancillary drug recommendations that were offered and accepted during the program realized a cost avoidance of $6613.75. CONCLUSIONS: This dosage adjustment program using pharmacodynamic principles was successful in optimization of dosing, potential minimization of morbidity caused by excessive dosing, and demonstration of direct and potentially indirect cost avoidance. A dosing program for patients with renal impairment would be of benefit to other clinicians and institutions seeking to optimize patient care.