Glucobay
acarbose
Pharmacologic class: Alpha-glucosidase inhibitor
Therapeutic class: Hypoglycemic
Pregnancy risk category B
Action
Improves blood glucose control by slowing carbohydrate digestion in intestine and prolonging conversion of carbohydrates to glucose
Availability
Tablets: 25 mg, 50 mg, 100 mg
Indications and dosages
➣ Treatment of type 2 (non-insulin-dependent) diabetes mellitus when diet alone doesn't control blood glucose
Adults: Initially, 25 mg P.O. t.i.d. Increase q 4 to 8 weeks as needed until maintenance dosage is reached. Maximum dosage is 100 mg P.O. t.i.d. for adults weighing more than 60 kg (132 lb); 50 mg P.O. t.i.d. for adults weighing 60 kg or less.
Contraindications
• Hypersensitivity to drug
• Renal dysfunction
• Type 1 diabetes mellitus, diabetic ketoacidosis
• GI disease
• Cirrhosis
• Colonic ulcers
• Inflammatory bowel disease
• Intestinal obstruction
• Pregnancy or breastfeeding
Precautions
Use cautiously in:
• patients receiving concurrent hypoglycemic drugs
• children.
Administration
• Give with first bite of patient's three main meals.
• Know that drug prevents breakdown of table sugar (sucrose). Thus, mild hypoglycemia must be corrected with oral glucose (such as D-glucose or dextrose), and severe hypoglycemia may warrant I.V. glucose or glucagon injection.
• Be aware that drug may be used alone or in combination with insulin, metformin, or sulfonylureas (such as glipizide, glyburide, or glimepiride).
Adverse reactions
GI: diarrhea, abdominal pain, flatulence
Metabolic: hypoglycemia (when used with insulin or sulfonylureas)
Other: edema, hypersensitivity reaction (rash)
Interactions
Drug-drug. Activated charcoal, calcium channel blockers, corticosteroids, digestive enzymes, diuretics, estrogen, hormonal contraceptives, isoniazid, nicotinic acid, phenothiazines, phenytoin, sympathomimetics, thyroid products: decreased therapeutic effect of acarbose
Digoxin: decreased digoxin blood level and reduced therapeutic effect Insulin, sulfonylureas: hypoglycemia
Drug-diagnostic tests. Alanine aminotransferase, aspartate aminotransferase: increased levels
Calcium, vitamin B6: decreased levels
Hematocrit: decreased
Patient monitoring
• Monitor patient for hypoglycemia if he's taking drug concurrently with insulin or sulfonylureas.
• Stay alert for hyperglycemia during periods of increased stress.
• Assess GI signs and symptoms to differentiate drug effects from those caused by paralytic ileus.
• Check 1-hour postprandial glucose level to gauge drug's efficacy.
• Monitor liver function test results. Report abnormalities so that dosage adjustments may be made as needed.
Patient teaching
• Inform patient that drug may cause serious interactions with many common medications, so he should tell all prescribers he's taking it.
• Teach patient about other ways to control blood glucose level, such as recommendations regarding diet, exercise, weight reduction, and stress management.
• Stress importance of testing urine and blood glucose regularly.
• Teach patient about signs and symptoms of hypoglycemia. Tell him that although this drug doesn't cause hypoglycemia when used alone, hypoglycemic symptoms may arise if he takes it with other hypoglycemics.
• Urge patient to keep oral glucose on hand to correct mild hypoglycemia; inform him that sugar in candy won't correct hypoglycemia.
• Inform patient that GI symptoms such as flatulence may result from delayed carbohydrate digestion in intestine.
• Advise patient to obtain medical alert identification and to carry or wear it at all times.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.