Miglitol (2 brand names, 1 dosage form, 1 route)
Available dosage forms: TABLET.
Routes of administration: ORAL.
Brand Names
- GLYSET
- MIGLITOL
Indications and Usage
Miglitol tablets are indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.
Dosage and Administration
There is no fixed dosage regimen for the management of diabetes mellitus with miglitol tablets or any other pharmacologic agent. Dosage of miglitol tablets must be individualized on the basis of both effectiveness and tolerance while not exceeding the maximum recommended dosage of 100 mg 3 times daily. Miglitol tablets should be taken three times daily at the start of each main meal. Miglitol tablets should be started at 25 mg, and the dosage gradually increased both to reduce gastrointestinal adverse effects and to permit identification of the minimum dose required for adequate glycemic control of the patient. During treatment initiation and dose titration, one-hour postprandial plasma glucose may be used to determine the therapeutic response to miglitol tablets and identify the minimum effective dose for the patient. Thereafter, glycosylated hemoglobin should be measured at intervals of approximately 3 months. The therapeutic goal should be to decrease both postprandial plasma glucose and glycosylated hemoglobin levels to normal or near normal by using the lowest effective dose of miglitol tablets, either as monotherapy or in combination with a sulfonylurea.
Contraindications
Miglitol tablets are contraindicated in patients with: •Diabetic ketoacidosis •Inflammatory bowel disease, colonic ulceration, or partial intestinal obstruction, and in patients predisposed to intestinal obstruction •Chronic intestinal diseases associated with marked disorders of digestion or absorption, or with conditions that may deteriorate as a result of increased gas formation in the intestine •Hypersensitivity to the drug or any of its components
Drug Interactions
Several studies investigated the possible interaction between miglitol and glyburide. In six healthy volunteers given a single dose of 5 mg glyburide on a background of 6 days treatment with miglitol (50 mg 3 times daily for 4 days followed by 100 mg 3 times daily for 2 days) or placebo, the mean C max and AUC values for glyburide were 17% and 25% lower, respectively, when glyburide was given with miglitol. In a study in diabetic patients in which the effects of adding miglitol 100 mg 3 times daily for 7 days or placebo to a background regimen of 3.5 mg glyburide daily were investigated, the mean AUC value for glyburide was 18% lower in the group treated with miglitol, although this difference was not statistically significant. Information on a potential interaction with glyburide was obtained from one of the large U.S. clinical trials (Study 7) in which patients were dosed with either miglitol or placebo on a background of glyburide 10 mg twice daily. At the 6-month and 1-year clinic visits, patients taking concomitant miglitol 100 mg 3 times daily exhibited mean C max values for glyburide that were 16% and 8% lower, respectively, compared to patients taking glyburide alone. However, these differences were not statistically significant. Thus, although there was a trend toward lower AUC and C max values for glyburide when co-administered with miglitol tablets, no definitive statement regarding a potential interaction can be made based on the foregoing three studies. The effect of miglitol (100 mg 3 times daily for 7 days) on the pharmacokinetics of a single 1000 mg dose of metformin was investigated in healthy volunteers. Mean AUC and C max values for metformin were 12% to 13% lower when the volunteers were given miglitol as compared with placebo, but this difference was not statistically significant. In a study with healthy volunteers, co-administration of either 50 mg or 100 mg miglitol 3 times daily together with digoxin reduced the average plasma concentrations
Mechanism of Action
In contrast to sulfonylureas, miglitol tablets do not enhance insulin secretion. The antihyperglycemic action of miglitol results from a reversible inhibition of membrane-bound intestinal α-glucoside hydrolase enzymes. Membrane-bound intestinal α-glucosidases hydrolyze oligosaccharides and disaccharides to glucose and other monosaccharides in the brush border of the small intestine. In diabetic patients, this enzyme inhibition results in delayed glucose absorption and lowering of postprandial hyperglycemia. Because its mechanism of action is different, the effect of miglitol tablets to enhance glycemic control is additive to that of sulfonylureas when used in combination. In addition, miglitol tablets diminish the insulinotropic and weight-increasing effects of sulfonylureas. Miglitol has minor inhibitory activity against lactase and consequently, at the recommended doses, would not be expected to induce lactose intolerance.
Overdosage
Unlike sulfonylureas or insulin, an overdose of miglitol tablets will not result in hypoglycemia. An overdose may result in transient increases in flatulence, diarrhea, and abdominal discomfort. Because of the lack of extra-intestinal effects seen with miglitol tablets, no serious systemic reactions are expected in the event of an overdose.