Outpatient drug oversupply at a teaching hospital in Thailand.

Background: A part of rising drug expenditure in Thailand was causedfrom drug oversupply, which was a result from policy of civil servants to get direct reimbursement from Ministry ofFinance.
Objective: Describe the problem oforal drug oversupply at outpatient service in a teaching hospital and determine the cost that affects hospital between October 1, 2008 and September 30, 2009.
Material and Method: Data of oral drug prescribing for outpatients were retrievedfrom the hospital database in the format of Microsoft Visual Fox Pro 9.0 and analyzed by Microsoft Access 2007. Two assessment methods are applied to estimate drug oversupply more than 30 days, by month and by year. In addition, September 2009 was selected to study for a pattern of monthly drug oversupply.
Results: Total oversupply expenditure for fiscal year 2009 was 56.9 million Baht when summedfrom monthly basis and 62.0 million when performed as a whole year. Oversupply expenditure was 2.12 to 2.73%per month in term of money and 2.91 to 3.46% in term of quantity. In September 2009, cardiovascular & hematopoietic system had the most oversupply. By brand of drug, the most frequently oversupply were Calcium carbonate (7.60%), Simvastatin (3.69%) and Omeprazole (3.20%). In term of money, the top three highest costs were for Atorvastatin (7.27%), Clopidogrel (6.83%) and Rosuvastatin (4.24%). By health schemes, patients under CSMBS trend to be the most of prescribed drug oversupply at 8.31% (3.21 million Baht in September 2009) with average number of oversupply per patient at 1.83 items and average day left per drug item at 61.83 days.
Conclusion: The most oversupply expenditures were for chronic diseases. These data will focus the problem for hospital administrators to plan for suitable strategy to control drug oversupply in their hospital.