Glucose Glucosidase inhibitors

Acarbose is a nonabsorbable a-glucosidase inhibitor which blocks the digestion of starch, sucrose, and maltose. The digestion of complex carbohydrates is delayed and occurs throughout the small intestine rather than in the upper part of the jejunum. Absorption of glucose and other monosaccharides is not affected. Acarbose is adrninistered orally three times a day and chewed with the first mouthful of food. 

When a-glucosidase activity is inhibited, carbohydrate digestion is prolonged and takes place further along the intestinal tract. This in turn delays and spreads the period of glucose absorption, which reduces the extent of the postprandial rise in blood glucose concentrations. The effectiveness of a-glucosidase inhibitors is dq en-dent on the consumption of a meal rich in complex carbohydrate. 

Acarbose (an a-glucosidase inhibitor) delays intestinal formation of glucose from disaccharides. 

II.f.2.1. Oral hypoglycaemic agents. There are now five groups of orally active drugs available to lower blood glucose in clinical practice (Table 2). These are sulphonylureas, biguanides, alpha-glucosidase inhibitors, thiazolidinediones, and the incretin derivatives. 

Alpha glucosidase inhibitors mainly reduced postprandial blood glucose and has a mean lowering of initial HbAlc of 0.5-1.0%. The major side effects are abdominal discomfort. Hence it is advised to begin with a low dose (25-50 mg) at the start of meals and increase slowly up to a dose of 100 mg three times daily, as judged by the patient s response. 

Alpha-glucosidase inhibitors are infrequently prescribed in the United States because of their prominent gastrointestinal adverse effects and relatively minor glucose-lowering benefit. 

Sato, K, Bokura, M, Moriyama, H, Igarashi, T, Total synthesis of a novel (i-glucosidase inhibitor, cyclophellitol starting from D-glucose, Chem. Lett., 37-40, 1994. 

Alpha-glucosidase inhibitor Inhibits alpha glucosidase, the digestive enzyme in the small intestine that is responsible for the release of glucose from the complex carbohydrates in the diet. 

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