Miglitol Side Effects

Medically reviewed by Drugs.com. Last updated on Mar 23, 2025.

Applies to miglitol: oral tablet.

Precautions

Your doctor will want to check your progress at regular visits, especially during the first few weeks that you take this medicine.

It is very important to follow carefully any instructions from your health care team about:

• Alcohol—Drinking alcohol may cause severe low blood sugar. Discuss this with your health care team.
• Other medicines—Do not take other medicines during the time you are taking miglitol unless they have been discussed with your doctor. This especially includes nonprescription medicines such as aspirin, and medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems.
• Counseling—Other family members need to learn how to prevent side effects or help with side effects if they occur. Also, patients with diabetes may need special counseling about diabetes medicine dosing changes that might occur because of lifestyle changes, such as changes in exercise and diet. Furthermore, counseling on contraception and pregnancy may be needed because of the problems that can occur in patients with diabetes during pregnancy.
• Travel—Keep a recent prescription and your medical history with you. Be prepared for an emergency as you would normally. Make allowances for changing time zones and keep your meal times as close as possible to your usual meal times.

In case of emergency—There may be a time when you need emergency help for a problem caused by your diabetes. You need to be prepared for these emergencies. It is a good idea to wear a medical identification (ID) bracelet or neck chain at all times. Also, carry an ID card in your wallet or purse that says that you have diabetes and a list of all your medicines.

Symptoms of hypoglycemia (low blood sugar) include anxiety; behavior change similar to being drunk; blurred vision; cold sweats; confusion; cool, pale skin; difficulty in thinking; drowsiness; excessive hunger; fast heartbeat; headache (continuing); nausea; nervousness; nightmares; restless sleep; shakiness; slurred speech; or unusual tiredness or weakness.

Miglitol does not cause low blood sugar. However, it can occur if you delay or miss a meal or snack, drink alcohol, exercise more than usual, cannot eat because of nausea or vomiting, or take miglitol with another type of diabetes medicine. Symptoms of low blood sugar must be treated before they lead to unconsciousness (passing out). Different people feel different symptoms of low blood sugar. It is important that you learn which symptoms of low blood sugar you usually have so that you can treat it quickly.

If symptoms of low blood sugar occur, eat glucose tablets or gel or honey, or drink fruit juice to relieve the symptoms. Table sugar (sucrose) or regular (nondiet) soft drinks will not work. Also, check your blood for low blood sugar. Glucagon is used in emergency situations when severe symptoms such as seizures (convulsions) or unconsciousness occur. Have a glucagon kit available, along with a syringe or needle, and know how to use it. Members of your household also should know how to use it.

Symptoms of hyperglycemia (high blood sugar) include blurred vision; drowsiness; dry mouth; flushed, dry skin; fruit-like breath odor; increased urination; ketones in urine; loss of appetite; stomachache, nausea, or vomiting; tiredness; troubled breathing (rapid and deep); unconsciousness; or unusual thirst.

High blood sugar may occur if you do not exercise as much as usual, have a fever or infection, do not take enough or skip a dose of your diabetes medicine, or overeat or do not follow your meal plan.

If symptoms of high blood sugar occur, check your blood sugar level and then call your health care professional for instructions.

Other side effects of miglitol

Some side effects of miglitol may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to miglitol: oral tablet.

General adverse events

The most commonly reported adverse reactions include gastrointestinal symptoms; they tend to diminish in frequency and intensity with time.

Gastrointestinal

• Very common (10% or more): Flatulence (41.5%), diarrhea (28.7%), abdominal pain (11.7%)
• Postmarketing reports: Pneumatosis cystoides intestinalis (may present with symptoms of diarrhea, mucus discharge, rectal bleeding, and constipation), ileus (including paralytic ileus), subileus, gastrointestinal pain, nausea, abdominal distention.^[Ref]

The severity of gastrointestinal symptoms may be decreased by dosage reduction and avoiding high gas-producing foods and sucrose. Some studies have demonstrated a decrease in the severity of gastrointestinal effects over time with continued administration.^[Ref]

Dermatologic

• Common (1% to 10%): Skin rash^[Ref]

Hematologic

• Common (1% to 10%): Low serum iron^[Ref]

See also:

Further information

Miglitol side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer