OBJECTIVES: Since 2011, the Centers for Medicare and Medicaid Services has required all long term care facilities to implement a short fill supply for all solid oral dosage forms in order to reduce medication wastage from medication discontinuation. The objective of this study was to evaluate potential savings that could be achieved from a 15-day initial fill policy for selected out-patient medications in the Mississippi Medicaid program. METHODS: A retrospective analysis was conducted using Mississippi Medicaid fee-for-service and managed care pharmacy claims data for the period January 1, 2013 through December 31, 2013. Oral drugs, costing more than $1000 per prescription, were evaluated for inclusion in the 15-day initial fill model. All new starts for these medications during the year were identified and analyzed for persistency and average amount paid. Medications were selected for further evaluation based on (a) 50+% of new starts stayed on therapy for 90+ days and (b) 5+% of new starts had discontinued therapy before 30 days. Drugs which were expected to generate the most savings from this policy were then identified for the final list for evaluating potential savings from a 15-day initial fill policy. RESULTS: A total of 19 unique drugs were included in the final analysis of potential savings from a 15-day initial fill policy. These drugs were associated with high costs per prescription and high discontinuation rates. Assuming savings of 15-days of therapy from all discontinuations, the total annual savings from these 19 drugs was estimated to be $23.3 million. A conservative estimate with savings from only 50% of discontinuations was an annual savings of $11.6 million. CONCLUSIONS: Results indicate substantial savings could be achieved from a 15-day initial fill policy for some outpatient medications. Further consideration of such a policy must take into account the specific disease state and potential problems in disruption of therapy.