What is this medication?

ACARBOSE (AY car bose) treats type 2 diabetes. It works by slowing down the breakdown of carbohydrates from the food you eat. This helps reduce your blood sugar (glucose). Changes to diet and exercise are often combined with this medication.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Precose

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Ketoacidosis
  • Kidney disease
  • Liver disease
  • Stomach or bowel disease, bowel obstruction
  • An unusual or allergic reaction to acarbose, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breast-feeding

How should I use this medication?

Take this medication by mouth with a glass of water. Follow the directions on the prescription label. Swallow the tablets at the start of a main meal. Take your doses at regular intervals. Do not take your medication more often than directed. Do not stop taking this medication except on the advice of your care team.

If you develop severe vomiting or severe diarrhea that prevents you from eating meals, call your care team for advice.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you forgot your dose at the start of your meal and you are still eating that meal, take your dose while you are still eating. Otherwise, skip the missed dose. This medication is not effective if not taken during a meal. Wait for your next dose at your next main meal, and take only that dose. Do not take double or extra doses.

What may interact with this medication?

  • Charcoal
  • Digestive enzymes like amylase and pancreatin
  • Digoxin
  • Diuretics
  • Female hormones, like estrogens or progestins and birth control pills
  • Isoniazid
  • Medications for colds or breathing difficulties like pseudoephedrine or phenylephrine
  • Medications for high blood pressure called beta-blockers and calcium channel-blockers
  • Nicotinic acid
  • Phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine
  • Phenytoin
  • Steroid medications like prednisone or cortisone
  • Thyroid hormones

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress.

A test called the A1C will be monitored. This is a simple blood test. It measures your blood sugar control over the last 2 to 3 months. You will receive this test every 3 to 6 months.

Learn how to check your blood sugar. Learn the symptoms of low and high blood sugar and how to manage them.

Always carry a quick-source of sugar with you in case you have symptoms of low blood sugar. An example is glucose tablets. Make sure others know that you can choke if you eat or drink when you develop serious symptoms of low blood sugar, such as seizures or unconsciousness. They must get medical help at once.

Tell your care team if you have high blood sugar. You might need to change the dose of your medication. If you are sick or exercising more than usual, you might need to change the dose of your medication.

Do not skip meals. Ask your care team if you should avoid alcohol. Many nonprescription cough and cold products contain sugar or alcohol. These can affect blood sugar.

It is important to follow a diabetic diet when taking this medication. This may help decrease some of the side effects like diarrhea, bloating, and gas. If you are following the diet and you still have severe diarrhea or gas, contact your care team.

Wear a medical ID bracelet or chain, and carry a card that describes your disease and details of your medication and dosage times.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Bloating
  • Diarrhea
  • Gas
  • Stomach pain

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children.

Store at room temperature below 25 degrees C (77 degrees F). Protect from moisture. Keep container tightly closed. Throw away any unused medication after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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