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Insert D: Glyset and Precose (Alpha-Glucosidase Inhibitors)

Alp​ha-Glucosidase (AL-fuh-gloo-KOH-sih-dayss)​ Inhibitor (​in-HIB-ih-tur)​

Brand Name​ ​Generic Name
​ __ Glyset (GLY-set)  __ miglitol (MIG-lih-tol)​
 __ Precose (PREE-kohss)​  __ acarbose (A-kahr-bohss)​

What does th​is type of pill do?

This type of pill helps keep your blood glucose from going too high after you eat, a common problem in people with diabetes. It works by slowing down the digestion of foods high in carbohydrate, such as rice, potatoes, bread, milk, and fruit.

Who should not ​take Glyset or Precose?

Talk with your doctor about whether to take this type of pill if

  • you have bowel disease or other intestinal conditions
  • you have advanced kidney or liver disease
  • you are pregnant, planning to get pregnant, or breastfeeding

What are the possible side​ effects?

This type of pill doesn't cause low blood glucose by itself. But your risk of having low blood glucose goes up if you also take

  • diabetes pills that cause low blood glucose
  • insulin

Your doctor may ask you to take a lower dose of your other diabetes medicines while you take this type of pill.

Taking Glyset or Precose may cause stomach pain, gas, bloating, or diarrhea. These symptoms usually go away after you have taken these pills for a while.

If you take Glyset or Precose: What ​you need to know about low blood glucose

If you take Glyset or Precose, only glucose tablets or glucose gel will bring your blood glucose level back to normal quickly. Other quick-fix foods and drinks won't raise your blood glucose as quickly because Glyset and Precose slow the digestion of other quick-fix foods and drinks.

Return to What I need to know about Diabetes Medicines

Go to Insert E: Glucophage, Glucophage XR, and Riomet (Biguanides)


This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings through its clearinghouses and education programs to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts.

This information is not copyrighted. The NIDDK encourages people to share this content freely.


December 2013​