Sulfonylureas are a type of antidiabetic drug used to treat diabetes mellitus type 2. These drugs stimulate the pancreas into secreting larger amounts of insulin to help remove sugars from the blood. Sulfonylureas are often prescribed in conjunction with other medications such as metformin or thiazolidinedione medications to improve the management of blood sugar levels.
Insulin is a hormone produced by the beta cells of the pancreas. This hormone is produced in response to blood sugar levels, for the purpose of allowing sugars to be taken up by cells that require energy. Type 2 diabetes develops as a result of insulin resistance, in which cells no longer respond to insulin. Sugars remain in the blood, causing inflammation and fluid loss in many parts of the body. The long-term consequences of uncontrolled high blood sugar include eye damage, nerve damage, heart disease and kidney disease.
Sulfonylureas work by binding to molecules on beta cells that increase the cellular concentration of calcium. An increased calcium level in beta cells causes them to release more insulin into the extracellular environment. There are many different sulfonylurea drugs, with considerable variance in terms of how long the drugs are active in the body. Some remain active for only a few hours and must be taken two or three times a day. Others are active for much longer and might need to be taken only once a day.
These medications are prescribed for people who have not been able to control their blood sugar levels with exercise, dietary modification and weight loss. Most people who have sulfonylureas prescribed to them find that they can achieve much better blood sugar control with a combination of diet, exercise and a sulfonylurea drug, compared to diet and exercise alone. These medications also decrease the long-term risk of nerve damage, eye damage and kidney damage caused by uncontrolled high blood sugar.
The most common side effect of sulfonylurea drugs is hypoglycemia, or low blood sugar. These medications also can cause weight gain, gastrointestinal upset and headaches. In addition, chronically increased levels of insulin can lead to an increased risk of heart disease.
Sulfonylurea medications are not considered safe for use by women who are pregnant or are planning to become pregnant. This is because the effects of these drugs on unborn babies are not known. In addition, women who are breast-feeding cannot use these medications. Insulin therapy generally is recommended for women who require blood sugar control during and after pregnancy. In addition, sulfonylureas cannot be used by people who have impaired kidney or liver function, because this impairment increases the risk that the medication will cause hypoglycemia.