Overview: Metformin is medicine you take to help keep your blood sugar from getting too high. Common side effects may include stomach problems, such as diarrhea, nausea, vomiting, stomach pain. Metformin is the most commonly prescribed medication for diabetes worldwide. In addition to lowering blood sugar, it has been linked to a wide range of positive health effects, including protection against tumors, inflammation, and atherosclerosis. Metformin is used to treat high blood sugar levels that are caused by a type of diabetes mellitus or sugar diabetes called type 2 diabetes. With this type of diabetes, insulin produced by the pancreas is not able to get sugar into the cells of the body where it can work properly. Metformin is approved to treat Type 2 diabetes. It’s also prescribed off-label for other uses, including prediabetes. Common metformin side effects include diarrhea, nausea, and vomiting. It can also cause fatigue, weight loss, and low vitamin B12 levels. Metformin is used alone or with other medications, including insulin, to treat type 2 diabetes (condition in which the body does not use insulin normally and, therefore, cannot control the amount of sugar in the blood). Metformin has long been used as a low-cost, daily prescription medication for treating Type 2 diabetes and high levels of insulin resistance. It belongs to a class of diabetes medications known as biguanides. It comes in immediate or extended-release formulations. Metformin is a generic prescription medication used to help manage blood sugar levels in adults and some children with type 2 diabetes. It works by decreasing sugar production in the liver. Metformin is an FDA-approved antidiabetic agent that manages high blood sugar levels in type 2 diabetes patients. It reduces glucose absorption from the intestines, lowers liver glucose production, and improves insulin sensitivity. Summary Millions take metformin every day to manage type 2 diabetes. The NHS has now issued a clear warning about symptoms that should never be ignored. Here is what the medicine is used for, common side effects, and the serious signs that mean you should contact a doctor or seek urgent help. Medical uses Metformin is used to lower blood glucose in those with type 2 diabetes. [15] It has also been used to help with metabolic abnormalities in polyendocrine metabolic ovarian syndrome (PMOS), and as a second-line agent for infertility in those with PMOS. [15][34].