1. Summary Pattern of Specific COX II Inhibitors Use Physician prescribed appropriate COX II use in high risk was 40.08% and inappropriate COX II use in low risk group was 59.92% Cost Waste COX II compared with NSAIDs in low risk for actual practice 2.4 million Baht/year. COX II compared with NSAIDs in low risk for standard treatment e.g., Diclofenac 3.4 million Baht/year, Voltaren ® 1.7 million Baht/year and Ibuprofen 400 mg 3.2 million Baht/year. Additional Cost NSAIDs compared with specific COX II inhibitors in high risk for actual practice: Celecoxib 1.5 million Baht/year, Rofecoxib 1.8 million Baht/year. Discussion In this study, the most frequent prescribing was specific COX II inhibitors plus GPA or NSAIDs plus GPA. The results of this study were different from a previous study conducted by Phochanukul (1999), which demonstrated that the most frequent prescribing pattern was specific COX II inhibitors alone or NSAIDs alone. In Thailand, Pharmaceutical and Therapeutic Committee (PTC) should develop and implement prior authorization policy for appropriate specific COX II inhibitors utilization in the hospital. This policy would help saving substantial amount of money in long term. Conclusion & Policy Recommendation Cost waste of specific COX II inhibitors in low risk group compared with NSAIDs was 2.4 million Baht/year in actual practice. Compared to Diclofenac, Voltaren  and Ibuprofen 400 mg, excessive expenditures were 3.4, 1.7, and 3.2 million Baht/year. Further study should focus on individual patient’s payment status to find our whether the payment status is a factor influencing physician prescribing. Pharmaceutical and Therapeutic Committee (PTC) should implement Drug Use Review (DUR) to evaluate specific COX II inhibitors use in clinical practice. The Clinical Practice Guideline (CPG) of specific COX II inhibitors should be reviewed in order to restrict specific COX II inhibitors use for high risk group only. Abstract Problem Statement: The inappropriate prescribing of specific COX II inhibitors (C2I) has economic impact on individual patient’s and overall health care cost. Objectives: To characterize the patterns of C2I use and to determine it’s cost impact in patients who were at low risk and high risk for gastrointestinal adverse effects. Designs: Retrospective design Settings: Lerdsin Hospital, the Institute of Orthopedics of Ministry of Public Health, Bangkok, Thailand. Study Population: Data from orthopedic outpatients having C2I and NSAIDs during November to December 2002 were collected. The proportionate sample was selected based on the two months drug utilization data including 519 prescriptions of C2I and 594 prescriptions of NSAIDs. To select the prescriptions, computerized simple random sampling was used. The National Institute for Clinical Excellence of United Kingdom Guidance for C2I use was employed to determine whether the patients receiving C2I were at high risk of GI adverse events. Outcome Measures: Total cost per prescription, average cost per prescription, average cost per day, mean duration of prescribed drug, and cost waste of C2I versus NSAIDs use in low risk group of actual practice and standard treatment. Additional cost of NSAIDs compared with C2I in high risk group of actual practice. Results: Two hundred and eight (40.1%) patients receiving C2I and 113 (19.0%) patients receiving NSAIDs were considered to be at high risk for upper GI adverse effects. Of the patients receiving prescriptions for C2I, 112 (21.6%) received C2I alone and 159 (30.6%) received Gastro-Protective Agents (GPA) in addition to C2I. The results showed that prescribing of C2I compared with NSAIDs among patients who were not at high risk of GI adverse events resulted in excessive expenditure of 2.4 million Baht/year. Compared with the three highest consumption drugs in the hospital including diclofenac, Voltaren®, and ibuprofen 400 mg, cost waste of C2I use were 3.4, 1.7 or 3.2 million Baht/year, respectively. The additional cost of NSAIDs compared with celecoxib or rofecoxib use in the high risk group, practice, were 1.5 or 1.8 million Baht/year, respectively. Conclusions: The cost impact of C2I use among patients who were at low risk for gastrointestinal adverse events compared with NSAIDs at Lerdsin Hospital was 2.4 million Baht/year. Because of the high cost impact of C2I use, it is necessary to employ clinical practice guideline for prescribing restriction and prospective drug use review for C2I. Funding Sources: Graduate Program in Social and Administrative Pharmacy and Graduate School of Chulalongkorn University Introduction Specific Cyclo-Oxygenase II (COX II) Inhibitors, have been introduced in several countries for the relief of chronic pain in rheumatoid arthritis and osteoarthritis. Celecoxib and rofecoxib are members of these specific COX II inhibitors, the incidence of gastric side effects with this new group is lower than observed in earlier NSAIDs. In Thailand, there had been an increasing trend of specific COX II inhibitors utilization; expenditures on celecoxib dramatically increased from 45.1 million Baht in 1999 to 295.6 million Baht while rofecoxib expenditures slightly increased from 20.1 million Baht in 1999 to 155.8 million Baht in 2001. The inappropriate prescribing of specific COX II inhibitors (COX II) has economic impact on individual patient’s and overall health care cost. Objectives To characterize the patterns of use of specific COX II inhibitors in orthopedic outpatients at Lerdsin Hospital. To determine cost impact of using specific COX II inhibitors in orthopedic outpatients who are in low risk and high risk GI adverse effects. Methods Research Design A retrospective Study during November 2002 to December 2002 in orthopedic outpatient clinic at Lerdsin Hospital, the Institute of Orthopedics of Ministry of Public Health, Bangkok, Thailand Subjects & Instrument Data from orthopedic outpatient prescriptions and OPD Card that having specific COX II inhibitors and NSAIDs was collected, including, patients’ characteristics, patients’ histories and physicians prescribing. Data collection form was used to be instrument of this study. SPSS was used for analyzing the data. Results Patient Characteristics Concerning age of patients, 35.1% of specific COX II inhibitors group and 15.3% of NSAIDs group were patients aged ≥ 65 years. From  2 test, there was an association between age and patient receiving specific COX II inhibitors. The result showed that, number of patients aged ≥ 65 years receiving specific COX II inhibitors more than number of patients aged ≥ 65 years receiving NSAIDs (P< 0.0001). Based on our observation, it appeared that the number of patient in CSMBS group received specific COX II inhibitors was greater than the number of patient who received NSAIDs. We conducted Chi Square test (  2) whether there was an association between CSMBS and patients receiving specific COX II inhibitors. The results showed that, the number of patients with CSMBS coverage receiving specific COX II inhibitors were greater than the others (P<0.0001). COST IMPACT OF USING SPECIFIC CYCLOOXYGENASE II INHIBITORS IN ORTHOPEDIC OUTPATIENTS AT LERDSIN HOSPITAL Jitsuda Phosri M.Sc. in Pharm., Assist. Prof. Vithaya Kulsomboon Ph.D., and Assist. Prof. Niyada Kiatying-Angsulee Ph.D. International Graduate Program in Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand Table 2:Cost Waste of Low Risk Group in Actual Practice and Standard Treatment COX-II+ NSAIDs Injection+ Other;3% COX-II+GPA +Other;31% COX-II Alone; 22% COX-II+Balm; 4% COX-II+ Analgesic;40% COX - II Alone COX - II + GPA + Other COX - II + NSAIDs Injection + Other COX - II + Analgesic COX - II + Balm Celecoxib Gr. Rofecoxib Gr. NSAIDs Gr. Total Cost (Baht) 77,589.12118,956.0626,776.67 Average Cost per prescription (Baht) 957.89 936.66236.96 Mean Duration (Days) 31.17 27.2421.36 Average Cost per Day Baht) 30.73 34.3911.21 Number of Prescriptions 81127113 Additional Cost (Baht/year) 1,536,033.4 8 1,824,039.78 - Additional Cost of High Risk Group in Actual Practice Table 1: Number of Prescriptions in Low Risk and High Risk for Upper GI Adverse Effects of Specific COX II Inhibitors and NSAIDs Using during November 2002 to December 2002 of Orthopedic Outpatients at Lerdsin Hospital. Figure 1: Pattern of Specific COX-II Inhibitors Use in Orthopedic Outpatient Department at Lerdsin Hospital Pattern of Drug Use Cost Waste of Low Risk Group in Actual Practice and Standard treatment Pattern of Drug Use in Low Risk and High Risk Group Table 3: Additional Cost of High Risk Group in Actual Practice