acarbose

An anti-diabetic drug used to treat diabetes mellitus type 2 and, in some countries, prediabetes.

It is a complex oligosaccharide of microbial origin and starch blocker, that competitively inhibits pancreatic alpha-amylase and alpha-glucosidases (glucoamylase, sucrase, maltase, and isomaltase) in the brush border of the small intestinal mucosa, which delays digestion of complex carbohydrates, delays absorption of glucose from the intestinal tract, and decreases postprandial blood glucose concentrations.

It prevents the degradation of complex carbohydrates into glucose, some carbohydrate will remain in the intestine and be delivered to the colon. In the colon, bacteria digest (ferment) the complex carbohydrates, causing flatulence (most of patients) and diarrhea (some patients).
(Side effects)
• flatulence
• diarrhea

It is significantly more effective in patients eating a relatively high carbohydrate Eastern diet.
It should be taken at the start of main meals.
The amount of complex carbohydrates in the meal will determine the effectiveness of acarbose in decreasing postprandial hyperglycemia.

The combination with metformin results in greater reductions of HbA1c, fasting blood glucose, and post-prandial glucose than either agent alone.

It is hydrolysed by enzymes produced by gut bacteria (e.g. maltogenic alpha-amylase from Thermus sp. IM6501, cyclomaltodextrinase from Lactobacillus plantarum). These bacteria inactivate this and create the resistance.