Generic name: Acarbose.

Precose is a diabetes drug classified as an alpha-glucosidase inhibitor. It works by slowing the body’s digestion of carbohydrates to keep blood sugar levels stable after a meal. It may be used safely in conjunction with insulin or other diabetes drugs such as Diabinese and Micronase.

Quick Facts About Precose


Used to treat Type II (non-insulin-dependent) diabetes when diet and exercise alone fail to control abnormally high blood sugar levels.

Precose Dosage

Take exactly as prescribed. Take orally 3 times daily with the first bite of each main meal. Carefully folllow dietary and exercise instructions from your doctor and take as prescribed.

  • Usual adult dose: initially — 25 milligrams (half of a 50-milligram tablet) 3 times per day with the first bite of each main meal. If necessary, your doctor will reevaluate dosage every 4 to 8 weeks, and increase dosage. Usually diabetes is controlled on 75 to 100 milligrams daily, but dosage may increase up to no more than 300 milligrams. For adults weighing less than 132 pounds — sustained dosage should never increase to over 150 milligrams (50 milligrams 3 times per day).
  • Usual child dose: not prescribed for children.
  • Missed dose: take as soon as possible, unless almost time for next dose. In that case, do not take missed dose; go back to regular schedule. Do not double doses.

Precose Side Effects

Overdose symptoms:

temporary increase in abdominal discomfort, diarrhea, gas. Will not cause hypoglycemia. If you suspect an overdose, immediately seek medical attention.

More common side effects: abdominal discomfort, diarrhea, increase in gas.

No known less common or rare Precose side effects.


Inform your doctor before combining Precose with:

airway-opening drugs such as Proventil and Sudafed; calcium channel blockers such as diltiazem (Cardizem) and nifedipine (Procardia); charcoal tablets; digestive enzyme preparations such as Creon 20 and Donnazyme; diuretics such as HydroDIURIL, Enduron, and Moduretic; estrogens (Premarin); isoniazid (Nydrazid); major tranquilizers such as Compazine and Mellaril; nicotinic acid (Nicobid and Nicolar); oral contraceptives; phenytoin (Dilantin); steroid medications such as prednisone (Deltasone) and prednisolone (Prelone); thyroid medications such as levothyroxine (Synthroid) and liotrix (Thyrolar).

No known food/other substance interactions.

Special Cautions

If pregnant or planning to become pregnant, inform g your doctor immediately. Your doctor may prescribe insulin therapy, which is safe during pregnancy. Not known if Precose appears in breast milk; could cause low blood sugar in nursing infant. Strictly adhere to dietary and prescribing instructions.

No special precautions apply to seniors.

Not prescribed for children.

  • Precose is not an oral form of insulin and cannot be used in place of insulin.
  • Precose does not cause low blood sugar (hypoglycemia) on its own; however, if taking in conjunction with insulin or other diabetes medications such as Diabinese or Glucotrol, blood sugar levels may fall too low. Symptoms of mild hypoglycemia include: cold sweat, fast heartbeat, fatigue, headache, nausea, nervousness. Symptoms of severe hypoglycemia include: coma, pale skin, shallow breathing. Contact your doctor immediately if the symptoms of hypoglycemia appear.
  • If taking other diabetes medications in conjunction with Precose, always carry a food product containing sugar (other than straight table sugar) to counter low-blood sugar symptoms.
  • Do not take to correct the following symptoms: excessive thirst, nausea, fatigue, and fruity breath. Yot may have diabetic ketoacidosis (a life-threatening medical emergency caused by insufficient insulin! which should be treated with insulin.
  • Check blood and urine regularly to test for liver reactions and for abnormally high sugar (glucose) levels. Effectiveness of any oral antidiabetic, including Precose, may decrease with time due to diminishec responsiveness to the medication or worsening or the diabetes.
  • For people with well-controlled diabetes, stress such as an injury, an infection, surgery, or a fever may trigger a loss of control. Your doctor may recommen: adding insulin to your
  • Precose treatment or replacing your Precose treatment temporarily with insulin.
  • Wear ID stating you are diabetic and whether or not you are insulin dependent.

Note: provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Precose side effects, please contact your healthcare provider