近來台灣老年人口急速增加，相對的老人用藥安全問題也成為目前很具重要的課題，老人照護在機構安養中心又因為環境與就業條件還未受到相對的重視，常常形成老人用藥安全的大漏洞，其中以重複用藥與不當用藥最為常見。 本研究目的就要以研究長照機構老人因為重複用藥與不當用藥所造成的用藥安全相關因素進行研究探討，以南部數間安養中心與護理之家進行資料分析透過依據stopp&start criteria(2013)與依ATC CODE分類建立檔案後，進行所有處方醫令與該資料檔比對分析找出符合條件的醫令藥品，在使用SPSS 12.0作統計，評估老年人潛在性可能不適當用藥，進行Logistic多項式回歸分析之相關危險因子。 得到以下結論:本研究以長照機構之健保申報資料檔，2014?2015年共7115處方箋張數，其中呈現65歲以上老年人處方箋有效張數有5046張數，男生佔2312人次(45.8%)，女生佔2734張數(54.2%)，以年齡區分65-74歲佔1148張數(22.8%)，75-84歲佔1887張數(37.4%)，85歲以上佔2011張數(39.9%)。 其中潛在性可能不適當用藥前3 種分別有Acetylsalicylic Acid，ntipsychotics，HMG CoA reductase inhibitors。可以藉由提出結論建議及討論，並可供未來從事老人用藥照護的參考與改善。 The elderly population has been increasing rapidly in these years. Medication safety in this populationhas become very important and urgent issue. Among them, the elderly population in long term care institutions has been neglected due to several reasons, such as social welfare, associated law, and low payments for caring people. This situation brought out some serious problems in the area of medication safety. Among safety issue of medication in the elderly, duplication and inappropriate usage were most common observed. The aims of this study were to explore possible risk factors that causing duplications and inappropriate medications that concern medication safety in long term care institutions. This study was conducted in several elder care and rehabilitation centers and nursing home in southern part of Taiwan.Medication information records were collected following Stopp&Start Criteria (2013). Data was categorized and compared to ATC CODE. Using comparative analysis method (SPSS VER12) to select the matching groups in ATC CODE.The research was conducted extensively the elderly potentially inappropriate medication assessment and the associated risk factors by Logistic regression analysis of polynomials.In this study, long term care institutions Bureau of National Health Insurance drug claims data files, a total of 7115 prescriptions between year 2014 and 2015 were collected. Among these, there were 5046 prescriptions used in age over 65 (age 65-74(22.8%), 75-84 (37.4%), and >85 years (39.9%)), and 2312for men (45.8%) and 2734for women (54.2%).The top 3 types of inappropriate medications were Acetylsalicylic Acid, Antipsychotis, and HMG CoA reductase inhibitors. This study could provide useful information for care of the elderly populations in the usage of medication in the future.