Products
Acarbose is commercially available in tablet form (Glucobay). It is usually combined with other agents such as metformin, insulin, or sulfonylureas to enhance the antidiabetic effect. Acarbose has been approved in many countries since 1986.
Structure and properties
Acarbose (C25H43NO18, Mr = 645.60 g/mol) is a pseudotetrasaccharide obtained from the bacterium by fermentation. It exists as a white to almost white powder that is soluble in water.
Effects
Acarbose (ATC A10BF01) has antihyperglycemic and antidiabetic properties by delaying the digestion of carbohydrates, thereby reducing blood glucose increases and blood glucose fluctuations after meals. Compared with metformin and sulfonylureas, the effect is weaker.
Mechanism of action
Effects are based on competitive and reversible inhibition of alpha-glucosidases in the brush border of the small intestine. Acarbose are false polysaccharides that bind to alpha-glucosidases, thereby inactivating them. Acarbose binds to the enzymes approximately 15,000 times more strongly than sucrose, for example.
Indications
Acarbose is used as an adjunctive treatment in patients with type 2 diabetes mellitus in whom diet or therapy with sulfonylureas or metformin is not sufficient.
Dosage
According to the SmPC. Acarbose is taken 3 times daily before each main meal.
Contraindications
- Hypersensitivity
- Severe renal insufficiency
- Chronic inflammatory bowel disease with digestive and absorption disorders.
- Conditions that may be worsened by increased gas formation in the intestines
For complete precautions, see the drug label.
Interactions
Acarbose is broken down primarily by intestinal bacteria and by digestive enzymes to inactive metabolites. A small fraction of these metabolites is absorbed and excreted in the urine. The effects of acarbose may be impaired if digestive enzyme preparations are taken at the same time, since these contain carbohydrate-splitting enzymes. Colestyramine also reduces the effects. Cane sugar and foods containing household sugar may increase intestinal discomfort and diarrhea due to increased carbohydrate fermentation. Caution is advised when combining with sulfonylureas, metformin, or insulin. Glucose levels may drop into the hypoglycemic range. Other interactions have been described with digoxin and neomycin. Acarbose may affect the bioavailability of digoxin. In the case of neomycin, an increased reduction in blood glucose levels after a meal has been observed. In both cases, dose adjustment should be considered.
Adverse effects
The most common adverse effects include digestive symptoms such as flatulence, bowel sounds, and diarrhea. They occur mainly at the beginning of treatment and may disappear during the course of treatment. The side effects occur as a result of bacterial fermentation of the undegraded carbohydrates in the intestine. Nausea, vomiting, and an increase in liver enzymes are also occasionally observed.