Alfa-Glucosidase Inhibitors

Alfa-Glucosidase Inhibitors


  • Alfa-Glucosidase Inhibitors are oral drugs for Type 2 Diabetes
  • These drugs inhibit the alfa-glucosidase enzymes in the small intestine
  • Alfa-Glucosidase Inhibitors interfere with the breakdown of carbohydrates & delays the absorption of glucose
  • Alfa-Glucosidase Inhibitors are less effective than other drugs in decreasing the A1C
  • Decreases A1C 0.5-1%
  • Must be taken with at the beginning of each meal to lower postprandial glucose levels
  • Do not give to patients with intestinal disease or GI obstruction
  • Do not give to patients with kidney or liver failure
  • Only antidiabetic agent whose effects do not depend on the presence of insulin
  • Reduces PPBS in type 1 & Type 2 diabetics
  • Arcabose decreases absorption of metformin


Drug Names

Acarbose-Precose, Miglitol-Glyset
Acarbose & Miglitol


Side Effects

  • Abdominal pain
  • Abdominal distension
  • Diarrhea
  • Flatulence
  • May cause hypoglycemia when combined with insulins
  • Long-term use may cause liver damage; LFT’s should be monitored q 3 months


Key Notes

  • If the patient is hypoglycemic and taking an Alfa-Glucosidase Inhibitor, it is important to treat the patient with glucose and not sucrose because sucrose is inhibited by Alfa-Glucosidase Inhibitor drugs.
  • Drugs that increase blood glucose: thiazide diuretics, glucocorticoids, alcohol, sympathomimetics, diltiazem, estrogens, morphine, nicotine, oral contraceptives, thyroid products.
  • Beta Blockers mask the symptoms of hypoglycemia and prevent hepatic glucose production.



Edmunds, M. W., & Mayhew, M. S. (2014). Pharmacology for the primary care provider (4th ed.). St. Louis, MO: Elsevier Mosby.

Harvey, R. A., Clark, M. A., Finkel, R., Rey, J. A., & Whalen, K. (2012). Pharmacology (5th ed.). Baltimore, MD: Lippincott.