正常腎功能下思覺失調症患者使用Metformin導致乳酸中毒之案例報告

Case Report of Metformin-Associated Lactic Acidosis, in a Patient with Schizophrenia with Normal Renal Function

Metformin是美國糖尿病學會、英國國家健康照護卓越機構與我國各專科醫學會明確建議的第二型糖尿病治療首選用藥，其不易導致低血糖，常見副作用多與腸胃道有關，例如：脹氣、腹部不適和腹瀉等。乳酸中毒是metformin罕見但致死率高達50%的嚴重不良反應，以往被認為好發於急性用藥過量或腎功能不良者。本文是一位65歲正常腎功能者在每日2000 mg合理用藥劑量下仍發生乳酸中毒的報告，所幸及時發現並停藥後個案得以恢復正常；文獻搜尋後，發現不只案例報告，亦有世代研究針對此議題作探討，相關資訊亦將在文中做陳述。

Metformin is the recommended first-line treatment for type 2 diabetes by ADA, NICE, and various medical societies in Taiwan. It is less likely to cause hypoglycemia, and common side effects mostly related to the gastrointestinal tract, such as bloating, abdominal discomfort, and diarrhea. Lactic acidosis is a rare but serious adverse reaction of metformin with a high mortality rate of up to 50%. It was previously believed to be more common in acute overdose or those with impaired renal function. This article reports a case of lactic acidosis in a 65-year-old patient with normal renal function despite being on a reasonable daily dose of 2000 mg of metformin. Fortunately, patient discovered in time and recovered after discontinuing the metformin. After literature search, not only case reports but also cohort studies on this issue were found, and relevant information will be presented in the article.(J Med Health. 2025;14(3):77-84)