居家個案因罹患多種慢性病、用藥量多、不只看一診及不只在一家醫院就醫，易導致有重複用藥及交互作用情形。專案小組於2009年6月至7月統計居家個案重複用藥或交互作用比率達61.7%。經現況分析確立問題為：一、護理人員四個月才檢視、記錄藥物一次，且對藥物間交互作用及重複用藥不清楚；二、缺乏藥師介入協助藥物諮詢；三、照顧者用藥認知不佳。經決策矩陣分析，實施下列對策：一、安排跨團隊藥物討論會討論個案用藥；二、更改護理師審視藥物頻率；三、增設藥品交互作用一覽表供護理人員參考；四、與藥師討論後針對重複用藥或交互作用之個案，建議當科醫師更改藥物；五、協同藥師針對交互作用或重複用藥個案進行家訪。方案實施後居家個案之重複用藥或交互作用比率由61.7%降低為13.7%，主要照顧者用藥安全認知亦明顯提升，顯示藉由跨團隊專業合作檢視個案用藥狀況，促使居家個案獲得更安全、完整的用藥環境，提升個案用藥安全。

Clients who receive home care may have duplicated medications which upon ingestion may create negative medicine interactive effect. These clients may have a history of many chronic diseases, requiring multiple medications. They usually have follow ups not only in one out-patient department and one hospital but many. The percentage of duplicated medications and interactions among home care patients was 61.7%. The main reasons included: 1) the registered nurses did not often check clients' medications and were not familiar with duplicated medications and interactions; 2) the pharmacists did not perform medicine counseling; 3) the communication between pharmacists and registered nurses was lacking; and 4) the caregivers did not have the appropriate knowledge of medication. According to the Policy-Making Matrix Analysis, we suggest to: 1) provide a multidiscipline case conference to discuss the medications of the clients; 2) increase the frequency of medication checks by registered nurses; 3) provide a list of medication interactive effects; 4) request different medications for the clients who demonstrate interactive effects, and 5) visit home care clients together with pharmacists. After implementing the above strategies, the rate of duplicated medications and interactions was decreased from 61.7% to 13.7%, and the knowledge of caregivers had significantly improved. The safety of medications use among home care patients was improved as well.