Trade Names:Glucovance- Tablets 1.25 mg/250 mg- Tablets 2.5 mg/500 mg- Tablets 5 mg/500 mg
Decreases blood glucose by stimulating insulin release from the pancreas and may decrease hepatic glucose production or increase response to insulin.Metformin
Decreases blood glucose by decreasing hepatic glucose production and may decrease intestinal absorption of glucose and increase response to insulin.
Adjunct to diet and exercise to improve glycemic control in patients with type 2 diabetes whose hyperglycemia cannot be satisfactorily managed by diet and exercise alone; second-line therapy when diet, exercise, and initial treatment with a sulfonylurea or metformin do not result in adequate glycemic control in patients with type 2 diabetes.
Patients with renal disease or dysfunction, which may also result from conditions such as CV collapse, acute MI, and septicemia; acute or chronic metabolic acidosis (including diabetic ketoacidosis, with or without coma); known hypersensitivity to any component of product.
Dosage must be individualized on the basis of efficacy and tolerance, while not exceeding the maximum recommended daily dose of glyburide 20 mg/metformin 2,000 mg.Initial TherapyAdults
PO Starting dose 1.25 mg/250 mg every day with a meal; if glycosylated hemoglobin is more than 9% or fasting plasma glucose is more than 200 mg/dL, start with 1.25 mg/250 mg twice daily with morning and evening meals. Dosage increases may be made in increments of 1.25 mg/250 mg per day every 2 wk up to the minimum effective dose (there is no experience with daily doses more than 10 mg/2,000 mg).Second-Line TherapyAdults
PO Start with 2.5 mg/500 mg or 5 mg/500 mg twice daily with morning and evening meals but not exceeding the daily dose of glyburide or metformin already being taken. Titrate the daily dose in increments of no more than 5 mg/500 mg up to the minimum effective dose.
Store at controlled room temperature (up to 77°F). Protect from light.
May potentiate the hypoglycemic action of glyburide.Alcohol
The effects of metformin on lactate metabolism may be potentiated. Disulfiram-like reactions have been reported rarely with glyburide.Bosentan
Increased metabolism of glyburide and decreased plasma levels of both bosentan and glyburide. Increased risk of serious liver injury.Calcium channel blocking agents, corticosteroids, estrogens, isoniazid, nicotinic acid, oral contraceptives, phenothiazines, phenytoin, sympathomimetics, thiazides and other diuretics, thyroid products
These agents tend to produce hyperglycemia and may lead to loss of blood glucose control.Cationic drugs (eg, amiloride, cimetidine, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, vancomycin)
May compete with metformin for renal tubular secretion, elevating metformin concentrations and increasing the pharmacologic effects.Cyclosporine
Cyclosporine concentrations may be elevated, increasing the pharmacologic effects and adverse reactions.Furosemide
Metformin plasma levels may be elevated while furosemide levels may be decreased.Nifedipine
Metformin plasma levels may be increased.Rifamycins (eg, rifampin)
Glyburide concentrations and t ½ may be decreased while Cl may be increased, increasing the risk of hyperglycemia.
None well documented.
Headache (9%); dizziness (6%).
Diarrhea (17%); nausea/vomiting (8%); abdominal pain (7%).
Upper respiratory infection (17%).
Lactic acidosis is a rare but serious metabolic complication that can be caused by metformin accumulation during treatment with glyburide/metformin. When it occurs, it is fatal in approximately 50% of cases.
Check blood sugar frequently and observe for signs of hypoglycemia. Monitor hemoglobin (HbA 1c ) every 3 months. Assess Hct, Hgb, and RbCs before starting therapy and periodically thereafter.
Assess renal function and verify as healthy before starting therapy and at least annually thereafter.
Monitor patient for signs or symptoms of metabolic acidosis (eg, abdominal pain, malaise, myalgia, nausea, respiratory distress, unexplained drowsiness, vomiting).
Category B . However, not recommended for use during pregnancy.
Safety and efficacy not established.
In general, elderly patients are not titrated to the max dose because of age-related decreases in renal function.
Decreased renal function results in decreased renal Cl and prolongation of the metformin t ½ . Concomitant medications that affect renal function may result in hemodynamic changes or interfere with disposition of metformin (eg, cationic drugs) and should be used with caution. Determine CrCl in patients older than 80 yr of age before initiating therapy.
Avoid use in patients whose serum creatinine levels exceed ULN for their age.
The administration of oral hypoglycemic drugs has been reported to be associated with increased CV mortality as compared with treatment with diet alone or diet plus insulin.
Avoid metformin in patients with clinical or laboratory evidence of hepatic disease.
Withhold metformin therapy at time of or prior to parenteral contrast studies with iodinated materials. Reinstitute therapy 48 h after the study and after renal function has been determined to be healthy.
Can occur as a result of metformin accumulation (eg, renal function impairment) or in pathophysiologic conditions associated with tissue hypoperfusion and hypoxia. The risk of lactic acidosis increases with the degree of renal function impairment and the age of the patient.
Hold therapy in patient undergoing surgical procedure until oral intake has resumed and renal function has been documented to be healthy.
A decrease in vitamin B 12 levels to subnormal may occur. Supplementation may be necessary.
Hypoglycemia, coma, neurological impairment, seizures.Metformin
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