Abstract: Prediabetes is a condition where blood glucose levels have deviated from the normal range but have not yet reached the diagnostic criteria for diabetes. It represents a transitional phase between health and diabetes. Currently，there are no global guidelines for managing prediabetes. However，the use of metformin in prediabetes is largely based on clinical experience，and there is a lack of high-quality evidence-based medicine. There are uncertainties regarding its dosage and unknown adverse reactions，and its exact efficacy and safety still require further study. This article systematically reviews the current state of metformin in the treatment of prediabetic，analyzing differences in efficacy across different dosages，the guideline recommendations，clinical application experiences，potential adverse effects and irrational drug use. We aim to provide scientific basis and clinical practice guidance for the rational use of metformin in the management of prediabetes.

Key words: Metformin, Prediabetes, Evidence-based medicine, Diabetes prevention, Rational use of medicines

摘要： 糖尿病前期是指血糖水平已经偏离参考范围但尚未达到糖尿病诊断标准的状态，处于健康与糖尿病之间的过渡阶段。目前，全球尚无针对糖尿病前期患者的药物治疗指南。二甲双胍作为 2 型糖尿病管理的首选药物，近年来被广泛应用于糖尿病前期患者的血糖调节治疗与糖尿病预防中，但二甲双胍在糖尿病前期的应用主要依赖于临床经验，尚缺乏高质量的循证证据，存在药物剂量使用不明确和不良反应未知的现况，其确切疗效与安全性仍需进一步深入研究。本文系统回顾了二甲双胍在糖尿病前期患者治疗现状，重点分析了不同剂型的药效差异、权威指南的推荐意见、临床应用的经验与观察、潜在不良反应以及不合理用药情况，旨在为糖尿病前期患者二甲双胍的合理用药提供科学依据和临床实践指导。

关键词: 二甲双胍, 糖尿病前期, 循证医学, 糖尿病预防, 合理用药