Effect of pharmacist intervention on the use of serum drug assays

The results of an investigation to (1) evaluate the use of serum drug assays (SDAs), (2) study the influence of clinical pharmacist monitoring and educational programs on SDA use, and (3) perform drug-related patient-care evaluations for the medical audit committee are reported. The components of the five-month study were a retrospective audit, education of physicians prescribing SDAs, and a concurrent reaudit. The four SDAs audited were digoxin, theophylline, gentamicin, and phenytoin. Criteria for appropriate use were defined by the audit committee and a clinical pharmacist. The criteria specified the indication for each drug, performance data, and dosage adjustments with SDA results. The clinical pharmacist presented two housestaff conferences on the appropriate use of SDAs and distributed educational materials to the attending physicians. An SDA report form was completed each time an SDA was ordered, and, whenever possible, the pharmacist met with the prescribing physician. Appropriate overall use of SDAs increased significantly (p less than 0.05). A significant improvement (p less than 0.05) was noted for each of the criteria. An estimated $2500 in patient charges was saved during the study; the cost of the clinical pharmacist's time was approximately $260. The authors concluded that clinical pharmacists, in conjunction with patient-care evaluations, can provide a cost-effective service in improving therapeutic patient monitoring based on SDA results.