DrugindexOnline^{2nd edition}

Pronouncation: (A-car-bose)
Class: Alpha-glucosidase inhibitor

Trade Names:
Precose
- Tablets 25 mg
- Tablets 50 mg
- Tablets 100 mg

Mechanism of Action

Pharmacology

Inhibits intestinal enzymes that digest carbohydrate, thereby reducing carbohydrate digestion after meals. This lowers postprandial glucose elevation in diabetics.

Pharmacokinetics

Absorption

Less than 2% is absorbed as active drug. T _max is approximately 1 h.

Metabolism

Metabolized within the GI tract by intestinal bacteria and digestive enzymes. At least 13 metabolites have been separated from urine specimens, with 1 being active.

Elimination

Less than 2% is recovered in the urine as active. The plasma elimination t _½ is approximately 2 h. Drug accumulation does not occur with 3 times daily oral dosing.

Special Populations

Renal Function Impairment

In those with Ccr less than 25 mL/min per 1.73 m ² , the C _max was approximately 5 times higher, and the AUC was 6 times larger. Treatment with acarbose is not recommended.

Elderly

AUC and C _max are approximately 1.5 times higher in the elderly, although not statistically significant.

Indications and Usage

Patients with non-insulin-dependent diabetes mellitus who have failed dietary therapy. May be used alone or in combination with sulfonylureas, insulin, or metformin.

Contraindications

Diabetic ketoacidosis; cirrhosis; inflammatory bowel disease; colonic ulceration; intestinal disorders of digestion or absorption; partial or predisposition to intestinal obstruction; conditions that may deteriorate as a result of increased intestinal gas production.

Dosage and Administration

Adults

PO 25 mg 3 times daily with the start of each meal. To minimize GI adverse reactions, some patients may benefit from more gradual dose titration. This may be achieved by initiating treatment at 25 mg daily and increasing the frequency to achieve 25 mg 3 times daily. Increase by 25 mg/dose at 4- to 8-wk intervals, according to response, up to a max based on blood glucose response (max, 150/day if no more than 60 kg, 300 mg/day if above 60 kg).

Storage/Stability

Store tablets at controlled room temperature (less than 77°F). Protect from moisture.

Drug Interactions

Drugs that produce hyperglycemia (eg, corticosteroids, diuretics, thyroid preparations), phenothiazines, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel-blocking drugs, isoniazid

May lead to loss of glucose control.

Intestinal adsorbents (eg, charcoal); digestive enzymes

May lower the efficacy of acarbose.

Laboratory Test Interactions

None well documented.

Adverse Reactions

GI

Flatulence (74%); diarrhea (31%); abdominal pain (19%).

Hepatic

Elevated serum transaminases rarely associated with jaundice.

Miscellaneous

Hypersensitivity skin reactions such as rash, edema (rare); decreased hematocrit; low serum calcium; low plasma vitamin B ₆ levels.

Precautions

Monitor Hypoglycemia Acarbose does not produce hypoglycemia; however, hypoglycemia may develop if used together with sulfonylureas or insulin. Check blood sugars frequently and observe for signs of hypoglycemia. Inform health care provider if blood sugar readings are outside target range or if hypoglycemic events are noted. Be prepared to treat hypoglycemic reactions with IV or oral glucose instead of cane sugar (table sugar) because absorption of cane sugar is inhibited by acarbose.

Pregnancy

Category B . Insulin is recommended to maintain blood glucose levels during pregnancy.

Lactation

Undetermined.

Children

Safety and efficacy not established.

Renal Function

Acarbose plasma concentrations may increase relative to the degree of renal function impairment.

Elevated serum transaminase levels

In long-term studies (up to 12 mo, and including acarbose doses up to 300 mg 3 times daily), treatment-emergent elevations of serum transaminases (AST and/or ALT) above ULN, greater than 1.8 times the ULN, and greater than 3 times the ULN occurred in acarbose-treated patients. Although these differences between treatments were statistically significant, these elevations were asymptomatic, reversible, more common in women, and, in general, were not associated with other evidence of liver dysfunction. Serum transaminase elevations appeared to be dose related. In studies including acarbose doses up to the max approved dose of 100 mg 3 times daily, treatment-emergent elevations of AST and/or ALT at any level of severity were similar between acarbose-treated patients and placebo-treated patients.

Loss of blood glucose control

Certain medical conditions (eg, surgery, fever, infection, trauma) and drugs (eg, diuretics, corticosteroids, oral contraceptives) affect glucose control. In these situations, it may be necessary to adjust dose of acarbose and other antidiabetic drugs.

Overdosage

Symptoms

Increased flatulence, diarrhea, abdominal discomfort.

Patient Information

• Educate patient regarding type 2 diabetes and its management, including target ranges for blood sugar control. Instruct patient that medication is not a substitute for diet and exercise and to continue to follow prescribed regimens.
• Educate patient or caregiver regarding potential long-term complications of diabetes and need for regular general physical and eye examinations.
• Advise patient to read patient information leaflet before starting therapy and with each refill.
• Advise patient to take prescribed dose at the start (ie, with the first bite) of each main meal.
• Advise patient that medication will be started at a low dose and then gradually increased as tolerated until max benefit is obtained.
• Advise patient to take as prescribed and not to stop taking or change the dose unless advised by health care provider.
• Advise patient to continue to take other medications for diabetes as prescribed by health care provider.
• Advise patient that GI adverse reactions (eg, gas, diarrhea, stomach discomfort) are common when therapy is started or the dose is increased, but that they should become less intense or frequent with continued therapy. Advise patient to inform health care provider if GI adverse reactions persist or become intolerable.
• Ensure that patient understands how to use home glucose monitor and has a plan for monitoring and recording blood sugar measurements (eg, log). Advise patient to take log to each visit with health care provider.
• Educate patient regarding value of periodic hemoglobin A1c testing to confirm level of glucose control.
• Advise patient to discuss with health care provider a plan for managing each of the following situations: medication dosing during intercurrent conditions (eg, vomiting, infection, trauma, stress, sick days); accidental administration of too little or too much medication; missed dose; inadequate food intake or a skipped meal; travel across time zones; change in physical activity.
• Advise patient to carry medical identification (eg, card, bracelet) of diabetes.
• Review symptoms of hypoglycemia and hyperglycemia and action plans to undertake in the event either occur. Caution patient to use only readily available sources of glucose (dextrose) for treatment of hypoglycemic reactions and to avoid using table sugar (cane sugar) because acarbose prevents cane sugar from being absorbed.
• Instruct patient to notify health care provider if experiencing hypoglycemic episodes or if measured blood sugars are outside target range.