Effects of acarbose on fecal nutrients, colonic pH, and short-chain fatty acids and rectal proliferative indices

Metabolism. 1996 Sep;45(9):1179-87. doi: 10.1016/s0026-0495(96)90020-7.


Acarbose, an alpha-glycosidase inhibitor, treats diabetes mellitus by delaying the digestion and intestinal absorption of dietary carbohydrates. In effective doses, acarbose induces some passage of carbohydrates into the colon. The effect of such chronic carbohydrate transfer on colonic structure and function is unknown. We studied the effects of 1 year of acarbose administration in diabetes mellitus on fecal energy, protein, and fat, including short-chain fatty acids (SCFA) output, fecal pH, and several metabolizing bacterial species. Changes in colonic histology and epithelial cell proliferation were investigated in rectal biopsies. Fecal macronutrient output was unaffected by acarbose, but pH decreased and total SCFA, butyrate, and acetate output were markedly greater. Breath hydrogen output increased after acarbose, but digoxin-metabolizing bacteria and diacylglycerol (DAG) production were unaltered. Compared with the control, acarbose did not induce hyperplasia or change rectal proliferation. However, total fecal SCFA and butyrate output correlated inversely with proliferation in the rectal upper crypt-a biomarker of risk for colonic neoplasia. In conclusion, long-term acarbose administration does not adversely affect colonic function or fecal nutrient output. If increased fecal SCFA and butyrate reduces upper-crypt proliferation, then acarbose may reduce the risk of colonic neoplasia.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Acarbose
  • Bacteria / isolation & purification
  • Bacteria / metabolism
  • Body Water
  • Cell Cycle
  • Cell Division
  • Colon / chemistry*
  • Digoxin / metabolism
  • Fatty Acids, Volatile / chemistry*
  • Feces / chemistry*
  • Feces / microbiology
  • Humans
  • Hydrogen-Ion Concentration
  • Hypoglycemic Agents / pharmacology*
  • Placebos
  • Rectum / cytology*
  • Trisaccharides / pharmacology*


  • Fatty Acids, Volatile
  • Hypoglycemic Agents
  • Placebos
  • Trisaccharides
  • Digoxin
  • Acarbose