[Comparative study of an expert system application in the prescription of medications]

The aim of this study was to evaluate the impact of a expert drug system implementation on the drug prescription habits and on drug cost in an university hospital.

During a 3 months period, the drug prescriptions to patients admitted to the Internal medicine, lung, gastroenterology and hepatology units, have been evaluated through the expert drug system (Medisource). This expert drug system functions in according to patients characteristics such as age, weight, height, sex, renal function and liver function. It recommends the correct dose, detects interactions and adverse effects and makes suggestions in pregnancy and lactation. It also offers alternative drugs with their cost. During the study period physicians were unaware of the investigation being performed.

836 patients (63.9 +/- 16.5 years) with an average hospital stay length of 11.6 +/- 6.7 days were studied. The most common diagnoses were: lung obstructive chronic disease, cirrhosis, gastrointestinal hemorrhage and cancer. The total amount of drug prescribed was 6,308. The expert system detected 458 overdosages and 33 underdosages, mainly in antibiotics and antiulcer drugs, and 1,722 interactions. The drug costs reduction that could be obtained following the expert system recommendations was 4.5% in antibiotic drugs and 23% in antiulcer drugs.

The frequency of drug overdosage and underdosage in patients admitted in an university hospital is relatively high. The expert systems available for drug decisions could solve this problem.