Article: Acarbose

Acarbose
Systematic (IUPAC) name
(2R,3R,4S,5R,6R)-5-[(2R,3R,4S,5R,6R)-5- [(2R,3R,4S,5R,6R)-3,4-dihydroxy-6-methyl- 5-[[(1S,4S,5S,6S)-4,5,6-trihydroxy-3-(hydroxy methyl)-1-cyclohex-2-enyl]amino]oxan-2-yl] oxy-3,4-dihydroxy-6-(hydroxymethyl)oxan- 2-yl]oxy-6-(hydroxymethyl)oxane-2,3,4-triol
Identifiers
CAS number	56180-94-0
ATC code	A10BF01
PubChem	441184
DrugBank	APRD00656
Chemical data
Formula	C25H45N3O16
Mol. weight	643.635 g/mol
Pharmacokinetic data
Bioavailability	Extremely low
Metabolism	Gastrointestinal tract
Half life	2 hours
Excretion	Renal (less than 2%)
Therapeutic considerations
Pregnancy cat.	B3 (Au), B (U.S.)
Legal status	POM (UK), ℞-only (U.S.)
Routes	Oral

Acarbose is a drug used to treat type 2 diabetes mellitus and, in some countries, prediabetes. It is sold in Europe under the brand name Glucobay® (Bayer AG), in North America as Precose® (Bayer AG), and in Canada as Prandase® (Bayer AG). It is an inhibitor of alpha glucosidase, an enteric enzyme that releases glucose from larger carbohydrates. The main side effect is loose stool or diarrhea, which limits its use, although these effects can be minimised by starting treatment with a low dose and titrating upwards. It is an effective anti-diabetic drug.

Acarbose inhibits enzymes needed to digest carbohydrates: specifically alpha-glucosidase enzymes in the brush broder of the small intestines and it inhibits pancreatic alpha-amylase. Pancreatic alpha-amylase hydrolyzes complex starches to oligosaccharides in the lumen of the small intestine, whereas the membrane-bound intestinal alpha-glucosidases hydrolyze oligosaccharides, trisaccharides, and disaccharides to glucose and other monosaccharides in 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)