Alpha-glucosidase inhibitors are saccharides that act as competitive inhibitors of enzymes needed to digest carbohydrates: specifically alpha-glucosidase enzymes in the brush border of the small intestines. The membrane-bound intestinal alpha-glucosidases hydrolyze oligosaccharides, trisaccharides, and disaccharides to glucose and other monosaccharides in the small intestine. Acarbose also blocks pancreatic alpha-amylase in addition to inhibiting membrane-bound alpha-glucosidases. Pancreatic alpha-amylase hydrolyzes complex starches to oligosaccharides in the lumen of the small intestine. Inhibition of these enzyme systems reduces the rate of digestion of complex carbohydrates. Less glucose is absorbed because the carbohydrates are not broken down into glucose molecules. In diabetic patients, the short-term effect of these drugs therapies is to decrease current blood glucose levels: the long term effect is a small reduction in hemoglobin-A1c level. (From Drug Therapy in Nursing, 2nd ed)
Voglibose, an alpha-glucosidase inhibitor, is a synthetic compound with potent and enduring therapeutic efficacies against disorders of sensory, motor and autonomic nerve systems due to diabetes mellitus. The drug was approved in Japan in 1994 for the treatment of diabetes, and it is under further investigation by Takeda for the treatment of impaired glucose tolerance. Alpha-glucosidase inhibitors are oral anti-diabetic drugs used for diabetes mellitus type 2 that work by preventing the digestion of complex carbohydrates (such as starch). Complex carbohydrates are normally converted into simple sugars (monosaccharides) which can be absorbed through the intestine. Hence, alpha-glucosidase inhibitors reduce the impact of complex carbohydrates on blood sugar.
Little metabolism occurs and no metabolites have as yet been identified.