Diarrhea, gas, or abdominal discomfort/pain may occur as your body adjusts to this medication during the first few weeks. These side effects usually lessen with time. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Miglitol does not usually cause low blood sugar (hypoglycemia). Low blood sugar may occur if this drug is prescribed with other diabetes medications, or if you do not consume enough calories from food, or if you do unusually heavy exercise. Talk with your doctor or pharmacist about whether the dose of your other diabetes medication(s) needs to be lowered.
Symptoms of low blood sugar include sudden sweating, shaking, fast heartbeat, hunger, blurred vision, dizziness, or tingling hands/feet. Do not use table sugar or drink non-diet soda to relieve these symptoms because miglitol slows the breakdown of table sugar. Carry glucose tablets or gel with you to treat low blood sugar. If you don't have these reliable forms of glucose, eat some honey or drink a glass of orange juice to quickly raise your blood sugar. Tell your doctor right away about the reaction and the use of this product. To help prevent low blood sugar, eat meals on a regular schedule and do not skip meals. Check with your doctor or pharmacist to find out what you should do if you miss a meal.
Symptoms of high blood sugar (hyperglycemia) include thirst, increased urination, confusion, drowsiness, flushing, rapid breathing, and fruity breath odor. If these symptoms occur, tell your doctor right away. Your dosage may need to be increased or you may need other drugs.
This medication may rarely cause a serious intestinal condition (pneumatosis cystoides intestinalis). Tell your doctor right away if you develop: diarrhea that doesn't stop, constipation, blood/mucus in stool.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.