Comparison of programs for preventing drug-nutrient interactions in hospitalized patients.

Three programs with different levels of pharmacist intervention designed to prevent drug-nutrient interactions (DNIs) were studied. Six drugs were selected for the study on the basis of their potential for involvement in significant DNIs and the hospital's drug-use profile. During a two-week control phase, the existing pharmacy system, in which no patient-specific information on DNIs is provided, was assessed. During the next four weeks, patients were randomly assigned to intervention 1, placement of a brightly colored label in the medication drawer and on the cover of the nursing medication card flip-chart, or to intervention 2, placement of the labels plus a five-minute structured patient-counseling session. Occurrence of DNIs and nurses' and patients' knowledge of DNIs were assessed. A DNI was defined as potentially altered drug absorption due to inappropriate timing or administration of a drug in relation to food. The occurrence of DNIs decreased significantly under the label system (from 24% to 19%) and under the combined label-counseling system (to 16%). However, the frequency of DNIs did not differ significantly between the two intervention groups. Patients' and nurses' knowledge of DNIs improved as a result of the interventions. The frequency of DNIs decreased when labels were used to alert nurses to proper medication timing.