Metformin is used for treating type II diabetes in adults and children. It may be used alone or in combination with other diabetic medications. Metformin also has been used to prevent the development of diabetes in people at risk for diabetes and to treat polycystic ovaries.
Metformin lowers blood glucose (sugar) and is used for treating type 2 diabetes. Insulin is a hormone produced by the pancreas that lowers glucose levels in blood by reducing the amount of glucose made by the liver and by increasing the removal of glucose from the blood by muscle and fat tissues. Diabetes results because of reduced production of insulin and reduced uptake (and effects) of insulin on the body's tissues. Metformin acts by increasing the sensitivity of liver, muscle, fat, and other tissues to the uptake and effects of insulin. These actions lower the level of sugar in the blood. Unlike glucose-lowering drugs of the sulfonylurea class, e.g. glyburide (Micronase; Diabeta) or glipizide (Glucotrol), metformin does not increase the concentration of insulin in the blood and, therefore, does not cause excessively low blood glucose levels (hypoglycemia) when used alone. In scientific studies, metformin reduced the complications of diabetes such as heart disease, blindness and kidney disease.
Metformin improves insulin sensitivity (increases peripheral glucose uptake and utilization), decreases the production of glucose by the liver, and decreases the absorption of glucose in the gut. Its use is contraindicated in patients with kidney disease or abnormalities, acidosis (disorders resulting in the production of lactic acid like diabetic ketoacidosis), and heart failure. Metformin possesses some distinct advantages in treating diabetes. Excess glucose produced by the liver is the major source of high blood sugars in Type 2 diabetes and is typically the reason for high blood sugars on waking in the morning. Metformin reduces this overproduction of glucose. It helps in lowering the blood sugar, especially after eating, with no risk of hypoglycemia when used alone. Modest improvement in cholesterol levels are also seen. The 10 year UKPDS Study of over 3,000 people with Type 2 diabetes found that those who were placed on metformin had a 36% decrease in overall mortality and a 39% decrease in heart attacks.