Therapeutic Drug Monitoring

Abstract

A pilot study done at our institution and previous studies in the literature indicate that therapeutic drug monitoring (TDM) is frequently performed without a proper indication. In addition, samples are often improperly collected or interpreted by physicians. The purpose of this study was to determine if a pharmacy-based educational intervention could positively influence the performance of TDM in a teaching institution. A cost-savings analysis on the reduction of drug levels not indicated or improperly sampled was also performed. The study consisted of a preliminary data collection period, an educational intervention, and a postintervention data collection period. The pre- and posteducational intervention periods consisted of a 1-month concurrent review of aminoglycosides, digoxin, and theophylline serum levels. The educational intervention consisted of in-service programs and newsletter. There were 188 and 211 serum drug levels analyzed during the pre- and postintervention periods, respectively. Overall, the educational intervention significantly increased the number of drug levels obtained for rational indications, correctly sampled and appropriately interpreted by physicians (p less than 0.001, chi 2 analysis). Cost savings associated with this program was +2,788 in patient charges (+559 in hospital costs) per month. This study demonstrated that TDM may be significantly improved through education.