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URL of this page: https://medlineplus.gov/druginfo/meds/a601079.html

Miglitol

pronounced as (mig' li tol)

Why is this medication prescribed?

Miglitol is used, alone or with other medications, to treat type 2 diabetes (condition in which the body does not use insulin normally and, therefore, cannot control the amount of sugar in the blood), particularly in people whose diabetes cannot be controlled by diet alone. It slows the breakdown and absorption of table sugar and other complex sugars in the small intestine. This process results in decreased blood sugar (hypoglycemia) levels following meals.

Over time, people who have diabetes and high blood sugar can develop serious or life-threatening complications, including heart disease, stroke, kidney problems, nerve damage, and eye problems. Taking medication(s), making lifestyle changes (e.g., diet, exercise, quitting smoking), and regularly checking your blood sugar may help to manage your diabetes and improve your health. This therapy may also decrease your chances of having a heart attack, stroke, or other diabetes-related complications such as kidney failure, nerve damage (numb, cold legs or feet; decreased sexual ability in men and women), eye problems, including changes or loss of vision, or gum disease. Your doctor and other healthcare providers will talk to you about the best way to manage your diabetes.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Miglitol comes as a tablet to take by mouth. It is usually taken three times a day with the first bite of a meal. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take miglitol exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

What special precautions should I follow?

Before taking miglitol,

  • tell your doctor and pharmacist if you are allergic to miglitol or any other drugs.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking miglitol. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • the following nonprescription product may interact with miglitol: ranitidine (Zantac). Be sure to let your doctor and pharmacist know that you are taking this medication before you start taking miglitol. Do not start this medication while taking miglitol without discussing with your healthcare provider.
  • tell your doctor if you have or have ever had a chronic intestinal disease, inflammatory bowel disease, intestinal obstruction, or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking miglitol, call your doctor.

What special dietary instructions should I follow?

Miglitol is used in combination with proper diet and exercise to control blood sugar. Skipping or delaying meals or exercising more than usual may cause your blood sugar to fall too low (hypoglycemia). Maintaining the diet and exercise program suggested by your doctor will ensure that the drug works properly.

Alcohol may cause a decrease in blood sugar. Ask your doctor about the safe use of alcoholic beverages while you are taking miglitol.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. Remember that miglitol should only be taken with a meal. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

When used in combination with insulin or other medications used to treat diabetes, miglitol may cause excessive lowering of blood sugar levels.

If you have any of the following symptoms, glucose products (Insta-Glucose or B-D Glucose tablets) should be used and you should call your doctor. Because miglitol blocks the breakdown of table sugar and other complex sugars, fruit juice or other products containing these sugars will not help to increase blood sugar. It is important that you and other members of your household understand this difference between miglitol and other medications used to treat diabetes.

  • shakiness
  • dizziness or lightheadedness
  • sweating
  • nervousness or irritability
  • sudden changes in behavior or mood
  • headache
  • numbness or tingling around the mouth
  • weakness
  • pale skin
  • hunger
  • clumsy or jerky movements

If hypoglycemia is not treated, severe symptoms may develop. Be sure that your family, friends, and other people who spend time with you know that if you have any of the following symptoms, they should get medical treatment for you immediately.

  • confusion
  • seizures
  • loss of consciousness

Call your doctor immediately if you have any of the following symptoms of hyperglycemia (high blood sugar):

  • extreme thirst
  • frequent urination
  • extreme hunger
  • weakness
  • blurred vision

If high blood sugar is not treated, a serious, life-threatening condition called diabetic ketoacidosis could develop. Call your doctor immediately if you have any of these symptoms:

  • dry mouth
  • upset stomach and vomiting
  • shortness of breath
  • breath that smells fruity
  • decreased consciousness

Miglitol may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • gas
  • diarrhea
  • stomach pain
  • skin rash

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and away and out of their sight and reach. https://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your blood sugar should be checked regularly to determine your response to miglitol. Your doctor will order certain lab tests to check your response to miglitol. Your doctor will also tell you how to check your response to this medication by measuring your blood or urine sugar levels at home. Follow these instructions carefully.

You should always wear a diabetic identification bracelet to be sure you get proper treatment in an emergency.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Glyset®
Last Revised - 06/20/2024