Class Name(s):

• 68:20.02 alpha-Glucosidase Inhibitors

Pronunciation:

• (mig' li tol)

Brand Name(s):

• Glyset^®¶; also available generically

WHY is this medicine prescribed?

Miglitol is 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). Miglitol in a class of medications called alpha-glucosidase inhibitors. It works by slowing the breakdown of carbohydrates from the food you eat in the small intestine. Slowing food digestion helps keep blood glucose from rising very high after meals.

HOW should this medicine be used?

Miglitol comes as a tablet to take by mouth. Take three times daily with the first bite of the meal. If you skip a meal, you need to skip the dose of miglitol.

Take miglitol exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor may start you on a low dose of miglitol and gradually increase your dose.

Miglitol controls diabetes but does not cure it. Continue to take miglitol even if you feel well. Do not stop taking miglitol without talking with your doctor.

Are there OTHER USES for this medication?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before taking miglitol,

• tell your doctor and pharmacist if you are allergic to this medication, any part of this medication, or any other medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
• you should know that some medications should not be taken with miglitol. Other medications may cause dosing changes or extra monitoring when taken with miglitol. Make sure you have discussed any medications you are currently taking or plan to take before starting miglitol with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking miglitol, please get the advice of your doctor or pharmacist.
• you should know the following nonprescription or herbal products may interact with miglitol: ranitidine, certain digestive enzymes (amylase, pancreatin), and charcoal. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking miglitol. Do not start these medications 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 diabetic ketoacidosis. Your doctor may tell you not to take miglitol.
• tell your doctor if you have or have ever had kidney disease, digestive issues, or surgery to your digestive tract.
• 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.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking miglitol.
• alcohol may cause a change in blood sugar. Ask your doctor about the safe use of alcoholic beverages while you are taking miglitol.
• you should know this medication may cause low blood sugar events if it is being used in combination with other blood sugar lowering medications. You should know the symptoms of low blood sugar (shakiness, nervousness, sweating, chills irritability, confusion, fast heart beat, feeling lightheaded or dizzy, hunger, headaches, nausea, blurred vision, or feeling weak). If you have these symptoms, consume about 15 grams of carbs [ex. half cup of juice or regular soda] every 15 minutes until your blood sugar has returned to normal.

What SPECIAL DIETARY instructions should I follow?

Be sure to follow all exercise and dietary recommendations made by your doctor or dietitian. It is important to eat a healthy diet, exercise regularly, and lose weight if necessary

What should I do IF I FORGET to take 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 should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at http://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.

Symptoms of overdose may include:

• increased gas
• diarrhea
• stomach upset

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).

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reach. http://www.upandaway.org

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to miglitol.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking miglitol.

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.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

^¶ This branded product is no longer on the market. Generic alternatives may be available.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™ Copyright, 2026. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: October 15, 2026.