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Acarbose

Brand names: Precose

Acarbose slows the digestion of carbohydrates to lower blood sugar after meals in type 2 diabetes.

Brand namesPrecose
Type of medicineAlpha-glucosidase inhibitor (diabetes medicine)
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

If low blood sugar happens with other medicines, treat it with glucose tablets; table sugar won't work well.

What it's used for

  • Type 2 diabetes

How to take it

  • Take it with the first bite of each main meal.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Gas
  • Bloating
  • Diarrhea
Call your provider todayYellow skin or eyes
Call your provider todaySevere belly pain

Warnings

  • Not for people with inflammatory bowel disease or bowel blockage.

Other medicines, foods, and alcohol

  • Insulin and sulfonylureas add to low blood sugar risk.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Talk with your provider.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.