Tolbutamide (brand name Orinase) is an anti-diabetic drug in the sulfonylureas class and the the first widely used sulfonylurea. It was approved by the FDA long back in 1957, and is sold against a medical prescription. It is administered to help control blood sugar and to treat type 2 diabetes. Generally, it is accompanied by appropriate diet and exercise. It is not used to treat type 1 diabetes. Tolbutamide stimulates the pancreas to produce more insulin which in turn leads to control of blood sugar level. This medication works only when pancreas are able to secrete insulin.
Using Tolbutamide may result into an allergic reaction like difficulty breathing; throat complication (closing of the throat); and swelling of the lips, tongue, or face. Other side effects are developing high blood sugar or low blood sugar - the symptoms for which should be watched carefully.
Certain precautions are required while using Tolbutamide including the following:
It is a prescription drug - prescribing health personnel should be made aware of other health condition of the patients like "kidney disease, liver disease, thyroid disease, type 1 diabetes, a serious infection, illness, or injury" etc.
Many other medicines, as indicated in the official website of Tolbutamide  , may increase or decrease the effect of this medicine.
Persons of 65 years or older may react strongly to this medicine, and may require lower dose.
It is a FDA pregnancy category C, meaning that its effect on the unborn baby is not known. It passes into breast milk that may cause hypoglycemia (low blood sugar) in a nursing baby.