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Alpha-Glucosidase Inhibitors for Type 2 Diabetes

Examples

Generic NameBrand Name
acarbosePrecose
miglitolGlyset

How It Works

Acarbose and miglitol help keep blood sugar levels within a target range by slowing the digestion of complex carbohydrates, also called starches. Complex carbohydrates include foods like bread, cereal, grain, pasta, rice, flour, beans, and vegetables like potatoes and corn. These medicines do not change the effect that simple sugars have on blood sugar. Simple sugars include foods like fruit, juice, milk, honey, desserts, and candy.

The medicine is taken with the first bite of food. These medicines do not cause the pancreas to produce more insulin. They will not cause low blood sugar (hypoglycemia) unless they are used with other oral medicines for diabetes or with insulin.

Why It Is Used

Alpha-glucosidase inhibitors help people with type 2 diabetes whose blood sugar is highest after eating complex carbohydrates.

The medicine may be used alone, with another medicine for diabetes, or with insulin.

How Well It Works

Type 2 diabetes is a disease that can get worse over time, so medicines may need to change. Diabetes medicines work best for people who are being active and eating healthy foods.

When taken with the first bite of food, these medicines have been found to lower blood sugar levels in people who have high blood sugar after eating (postprandial hyperglycemia). Studies have suggested that alpha-glucosidase inhibitors lower hemoglobin A1c by 0.5% to 0.8%.1

Side Effects

All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.

Here are some important things to think about:

  • Usually the benefits of the medicine are more important than any minor side effects.
  • Side effects may go away after you take the medicine for a while.
  • If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.

Call911or other emergency services right away if you have:

Call your doctor if you have:

Common side effects of this medicine include:

  • Passing of gas.
  • Feeling bloated.
  • Belly pain.
  • Diarrhea.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

These medicines do not cause low blood sugar or weight gain, but you might have low blood sugar if you don't eat or if you exercise, drink alcohol, or use another medicine that causes low blood sugar. When taking this medicine, low blood sugar can be treated with quick-sugar foods except table sugar or regular soda pop, which will not work.

If you pass a lot of gas while taking this medicine, your doctor may suggest a lower dose and then increase the dose slowly. Eating a lower-carbohydrate diet can also help. If you have problems with your digestive system, you might not be able to take this medicine.

Taking medicine

Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.

There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.

Advice for women

If you are pregnant, breast-feeding, or planning to get pregnant, do not use any medicines unless your doctor tells you to. Some medicines can harm your baby. This includes prescription and over-the-counter medicines, vitamins, herbs, and supplements. And make sure that all your doctors know that you are pregnant, breast-feeding, or planning to get pregnant.

Checkups

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.

Citations

  1. American Diabetes Association (2009). Medical management of hyperglycemia in type 2 diabetes: A consensus algorithm for the initiation and adjustment of therapy. Diabetes Care, 32: 193–203.

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerJennifer Hone, MD - Endocrinology, Diabetes and Metabolism
Last RevisedMay 2, 2012

WebMD Medical Reference from Healthwise

Last Updated: May 02, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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