Acarbose is an oligosaccharide antidiabetic agent.
Pharmacology: Mechanism of Action: The antihyperglycemic action of acarbose results from a competitive, reversible inhibition of pancreatic α-amylase complex starches to oligosaccharides in the lumen of the small intestine, while the membrane-bound intestinal and membrane-bound intestinal α-glucoside hydrolase enzymes. Pancreatic α-amylase hydrolyzes complex starches to oligosaccharides in the lumen of the small intestine, while the membrane-bound intestinal α-glucosidases hydrolyze oligosaccharides, trisaccharides and disaccharides to glucose and other monosaccharides in the brush border of the small intestine. In diabetic patients, this enzyme inhibition results in a delayed glucose absorption and a lowering of postprandial hyperglycemia.
Pharmacokinetics: Following oral dosing of healthy volunteers with 14C-labeled acarbose, peak plasma concentrations of radioactivity were attained 14-24 hrs after dosing, while peak plasma acarbose, concentrations of active drug were attained at approximately 1 hr. The delayed absorption of acarbose-related radioactivity reflects the absorption of metabolites that may be formed by either intestinal bacteria or intestinal enzymatic hydrolysis.
Acarbose is metabolized exclusively within the gastrointestinal tract, principally by intestinal bacteria.
The fraction of acarbose that is absorbed as intact drug is almost completely excreted by the kidneys.