General
Macrovascular Outcomes
There have been no clinical studies establishing conclusive evidence of macrovascular risk reduction with Acarbose Tablets or any other anti-diabetic drug.
Hypoglycemia
Because of their mechanism of action, Acarbose Tablets when administered alone should not cause hypoglycemia in the fasted or postprandial state. Sulfonylurea agents or insulin may cause hypoglycemia. Because Acarbose Tablets given in combination with a sulfonylurea or insulin will cause a further lowering of blood glucose, it may increase the potential for hypoglycemia. Hypoglycemia does not occur in patients receiving metformin alone under usual circumstances of use, and no increased incidence of hypoglycemia was observed in patients when Acarbose Tablets were added to metformin therapy. Oral glucose (dextrose), whose absorption is not inhibited by Acarbose Tablets, should be used instead of sucrose (cane sugar) in the treatment of mild to moderate hypoglycemia. Sucrose, whose hydrolysis to glucose and fructose is inhibited by Acarbose Tablets, is unsuitable for the rapid correction of hypoglycemia. Severe hypoglycemia may require the use of either intravenous glucose infusion or glucagon injection.
Elevated Serum Transaminase Levels
In long-term studies (up to 12 months, and including Acarbose Tablets doses up to 300 mg t.i.d.) conducted in the United States, treatment-emergent elevations of serum transaminases (AST and/or ALT) above the upper limit of normal (ULN), greater than 1.8 times the ULN, and greater than 3 times the ULN occurred in 14%, 6%, and 3%, respectively, of Acarbose Tablets-treated patients as compared to 7%, 2%, and 1%, respectively, of placebo-treated patients. Although these differences between treatments were statistically significant, these elevations were asymptomatic, reversible, more common in females, and, in general, were not associated with other evidence of liver dysfunction. In addition, these serum transaminase elevations appeared to be dose related. In US studies including Acarbose Tablets doses up to the maximum approved dose of 100 mg t.i.d., treatment-emergent elevations of AST and/or ALT at any level of severity were similar between Acarbose Tablets-treated patients and placebo-treated patients (p ≥ 0.496).
In approximately 3 million patient-years of international postmarketing experience with Acarbose Tablets, 62 cases of serum transaminase elevations > 500 IU/L (29 of which were associated with jaundice) have been reported. Forty-one of these 62 patients received treatment with 100 mg t.i.d. or greater and 33 of 45 patients for whom weight was reported weighed < 60 kg. In the 59 cases where follow-up was recorded, hepatic abnormalities improved or resolved upon discontinuation of Acarbose Tablets in 55 and were unchanged in two. Cases of fulminant hepatitis with fatal outcome have been reported; the relationship to acarbose is unclear.
Loss of Control of Blood Glucose
When diabetic patients are exposed to stress such as fever, trauma, infection, or surgery, a temporary loss of control of blood glucose may occur. At such times, temporary insulin therapy may be necessary.
Information for Patients
Patients should be told to take Acarbose Tablets orally three times a day at the start (with the first bite) of each main meal. It is important that patients continue to adhere to dietary instructions, a regular exercise program, and regular testing of urine and/or blood glucose.
Acarbose Tablets themselves do not cause hypoglycemia even when administered to patients in the fasted state. Sulfonylurea drugs and insulin, however, can lower blood sugar levels enough to cause symptoms or sometimes life-threatening hypoglycemia. Because Acarbose Tablets given in combination with a sulfonylurea or insulin will cause a further lowering of blood sugar, it may increase the hypoglycemic potential of these agents. Hypoglycemia does not occur in patients receiving metformin alone under usual circumstances of use, and no increased incidence of hypoglycemia was observed in patients when Acarbose Tablets were added to metformin therapy. The risk of hypoglycemia, its symptoms and treatment, and conditions that predispose to its development should be well understood by patients and responsible family members. Because Acarbose Tablets prevent the breakdown of table sugar, patients should have a readily available source of glucose (dextrose, D-glucose) to treat symptoms of low blood sugar when taking Acarbose Tablets in combination with a sulfonylurea or insulin.
If side effects occur with Acarbose Tablets, they usually develop during the first few weeks of therapy. They are most commonly mild-to-moderate gastrointestinal effects, such as flatulence, diarrhea, or abdominal discomfort, and generally diminish in frequency and intensity with time.
Laboratory Tests
Therapeutic response to Acarbose Tablets should be monitored by periodic blood glucose tests. Measurement of glycosylated hemoglobin levels is recommended for the monitoring of long-term glycemic control.
Acarbose Tablets, particularly at doses in excess of 50 mg t.i.d., may give rise to elevations of serum transaminases and, in rare instances, hyperbilirubinemia. It is recommended that serum transaminase levels be checked every 3 months during the first year of treatment with Acarbose Tablets and periodically thereafter. If elevated transaminases are observed, a reduction in dosage or withdrawal of therapy may be indicated, particularly if the elevations persist.
Monitoring glycemic control with 1,5-AG assay is not recommended as measurements of 1,5-AG are unreliable in assessing glycemic control in patients taking acarbose. Use alternative methods to monitor for glycemic control.
Renal Impairment
Plasma concentrations of Acarbose Tablets in renally impaired volunteers were proportionally increased relative to the degree of renal dysfunction. Long-term clinical trials in diabetic patients with significant renal dysfunction (serum creatinine > 2.0 mg/dL) have not been conducted. Therefore, treatment of these patients with Acarbose Tablets is not recommended.