OBJECTIVES: To examine if the introduction of a lump sum reimbursement system for pharmaceuticals in Belgian hospitals for hospitalized patients resulted in shifts in Health Insurance expenses (third party payer) for pharmaceuticals from an in-patient setting (hospitalized patients) to an out-patient setting (day clinic, public pharmacies,…), based on an analysis of financial data of NIHDI. METHODS: In july 2006, a partial (approximately 75 % of the expenses) lump sum reimbursement system was introduced for standard medication (excluding new expensive drugs, oncolytics, orphan drugs,…) fixing budgets per hospital, per hospitalization, based on patient profiles (APRDRG, All patients Refined Diagnosis Related Groups) and financial data. Using registered financial data from NIHDI the evolution of the Health Insurance expenses for pharmaceuticals in hospitals was examined. RESULTS: The yearly expenses for pharmaceuticals for hospitalized patients grew with +8.0%, +0.2%, -2.0%, -0.1% and +1.6% in the period 2003-2008.  For patients in day clinic the growth was respectively +23.7%, +11.7%, +5.8%, +19.3% and + 17,9%. For patients in public pharmacies these figures were +8.2%, +1.2%, -2.3%, +6.2% and +12.2%. CONCLUSIONS: Evaluation of the data shows no changes in the trend in evolution of the expenses for any type of patients other than leveling of the growth in the period 2005-2006 - similar to the evolution of expenses for pharmaceuticals in the other OECD countries - and a additional growth in expenses in public pharmacies (+ 6,2 %) due to the inclusion of self-employed persons in the general system for compulsory health insurance in 2008. Analysis shows no shifts in expenses from one setting to another.