Widely used overseas to treat type 2 diabetes, acarbose is less common in the U.S., due to side effects that may outweigh the benefits. It’s part of a class of medicines known as alpha-glucosidase inhibitors. In Europe and China, it’s available as a generic drug by the name of Glucobay. In the U.S. it’s marketed as Precose (by Bayer Pharmaceuticals), and in Canada it’s sold as Prandase. It works by blocking starch and inhibiting the enzyme that releases glucose from complex carbohydrates. This reduces the rate of digestion, and the blood therefore absorbs less glucose. The result is lower blood sugar levels and eventually lower Hb1ac levels. However, the drug’s action leaves some of the carbohydrates undigested in the intestine, which attracts bacteria and yeast and causes gastrointestinal symptoms such as diarrhea, bloating, nausea, vomiting, abdominal pain and flatulence. This can add to other uncomfortable symptoms of diabetes. Acarbose can …