OBJECTIVES: The polypharmacy were incidence increase risk of drug-drug interactions, especial suffers from elderly and chronic disease such as age greater than 60 years old, chronic kidney dysfunction, cardiovascular disease and cancers are significant. To evaluate the cost-effectiveness of consultations by pharmacists based within primary care polypharmacy in chronic disease. METHODS: In order to avoid duplication and waste treatment drugs, the plan is to be �wPharmaceutical Care System�xand to search medication information at Department of National Health Insurance Virtual Private Cloud (VPC). We were identifying potential duplicate medication from patients with polypharmacy, and to evaluated pharmacist consultations on health service use outcome. The study subjects were identified based on inappropriate prescriptions of duplicate medications, drug-drug interactions, or over-dosage. Chi-square test was used for pharmacist consultations on health service and cost-effectiveness of data analysis. RESULTS: A total of 68 patients on health service with pharmacist consultations were included in this study. The total direct medical costs for 24 patients were NT$3,4480 dollars and improved polypharmacy related adverse reaction. CONCLUSIONS: To develop pharmacist consultations on health service is helpful of increase communication and interaction with the professional skills of pharmacists and physicians to achieve consensus professional and is likely to save costs.