Impact of metformin on hypertension; current knowledge

High blood pressure is a potential adjustable risk factor for vascular complications of diabetes. Numerous categories of anti-hypertensive medications have proven to effectively reduce these complications. Additionally, metformin, besides lowering glucose and lipid levels, has advantages on vascular blood flow and improving endothelial function. In this review, we investigate the potential benefits of metformin in lowering blood pressure. Previous studies suggested that the administration of metformin to non-diabetic patients could efficiently reduce systolic blood pressure. The whole comparison of the evidence shows that metformin may have small effects on lowering blood pressure; however, this effect is not directly via a change in sympathetic activity. Mechanisms of blood pressure reduction by metformin may be due to its indirect effects on insulin resistance, nephroprotective, cardioprotective, improvement of the sympatric nerve system, and endothelial function.