Lee A J
School of Pharmacy, University of the Pacific, San Francisco, California, USA.
Pharmacotherapy. 1996 May-Jun;16(3):327-51.
Metformin is an oral antihyperglycemic agent that is approved by the Food and Drug Administration for the treatment of noninsulin-dependent diabetes mellitus. It differs from the sulfonylureas in that it is does not enhance insulin secretion and normally does not produce hypoglycemia. Metformin acts to decrease preprandial and postprandial blood glucose concentrations by increasing skeletal muscle uptake of glucose, decreasing gluconeogenesis, and decreasing absorption of glucose. The addition of metformin to maximum dosages of a sulfonylurea may synergistically improve glucose control. The drug may offer other potential benefits, such as weight loss or minimal weight gain, improved blood flow in patients with peripheral vascular disease, reduction of tissue plasminogen activator inhibitor, and improved lipid profiles. It is relatively safe if taken appropriately. Its most common side effects are gastrointestinal (nausea, diarrhea, anorexia), metallic taste, and vitamin B12 malabsorption. Lactic acidosis may also occur, but it is rare if metformin is avoided in patients with contraindications to its use. With careful monitoring, the agent may be considered for the initial treatment of obese patients who fail dietary measures, and those whose disease is refractory to maximum dosages of sulfonylureas or who do not tolerate them.
二甲双胍是一种口服降糖药，已获美国食品药品监督管理局批准用于治疗非胰岛素依赖型糖尿病。它与磺脲类药物不同，不会促进胰岛素分泌，通常也不会导致低血糖。二甲双胍通过增加骨骼肌对葡萄糖的摄取、减少糖异生以及减少葡萄糖吸收来降低餐前和餐后血糖浓度。在磺脲类药物最大剂量基础上加用二甲双胍可能会协同改善血糖控制。该药可能还有其他潜在益处，如减轻体重或体重增加极少、改善外周血管疾病患者的血流、降低组织纤溶酶原激活物抑制剂水平以及改善血脂状况。如果合理服用，它相对安全。其最常见的副作用是胃肠道反应（恶心、腹泻、厌食）、金属味和维生素B12吸收不良。乳酸酸中毒也可能发生，但如果对有使用禁忌的患者避免使用二甲双胍，则很少出现。经过仔细监测，对于饮食控制失败的肥胖患者、对磺脲类药物最大剂量治疗无效或不耐受的患者，可考虑将该药作为初始治疗药物。
