Glucovance (glyburide/metformin)

• Glucovance (glyburide/metformin) is a combination antidiabetic medication containing glyburide and metformin. Glucovance is used to improve blood glucose (sugar) control in adults with type 2 diabetes mellitus.
• Glyburide is a second generation oral sulfonylurea. It helps to lower blood glucose by stimulating the release of insulin, the hormone responsible for regulating blood glucose.
• Metformin is an oral biguanide antidiabetic agent. It decreases the production of glucose in the liver, decreases the absorption of glucose by the intestines, and increases the uptake and use of blood glucose by cells throughout the body.
• In clinical studies, glyburide/metformin therapy was observed to be superior in improving fasting plasma glucose, post-meal blood glucose, and HbA1c levels versus treatment with glyburide or metformin alone.
• Glucovance was approved by the FDA in July, 2000.

What brand names are available for glyburide/metformin tablets?

Glucovance

Is glyburide/metformin tablets available as a generic drug?

Yes

Do I need a prescription for glyburide/metformin tablets?

Yes

Glucovance is used as an adjunct to diet and exercise to improve blood glucose control in adults with type 2 diabetes.

The most common side effects include

• stomach pain,
• diarrhea,
• upset stomach,
• nausea,
• vomiting,
• headache, and
• dizziness.

Other commonly reported side effects with Glucovance therapy include

• decreased appetite,
• metallic taste,
• gas,
• heartburn, and
• weight loss.

Other side effects include

• hypoglycemia (low blood glucose),
• blood disorders,
• decrease blood sodium levels,
• rash,
• sensitivity to the sunlight,
• itching,
• liver disease,
• SIADH,
• hives, and
• hypersensitivity type reactions.

Metformin can cause a rare but serious condition known as lactic acidosis, a build-up of acid in the blood. Lactic acidosis can cause death and requires immediate treatment. Symptoms of lactic acidosis include

• tiredness,
• weakness,
• unusual
• muscle pain,
• pain in the stomach,
• difficulty breathing,
• dizziness, and
• slow or irregular heartbeat.

Patients suspected of having signs or symptoms of lactic acidosis must seek emergency medical help.

• For patients inadequately controlled on diet and exercise
  • Generally, the recommended starting dose of Glucovance is 1.25/250 mg administered once daily with a meal.
  • A starting dose of 1.25/ 250 mg twice daily may be considered for patients with HbA1c >9% or fasting plasma glucose (FPG) >200 mg/dL.
  • If necessary, dosage may be increased in increments of 1.25/250 mg at two week intervals.
  • The maximum daily dose of Glucovance is 20/2000 mg.
• For patients inadequately controlled on a sulfonylurea and/or metformin
  • Generally, the recommended starting dose of Glucovance is 2.5 mg/500 mg or 5 mg/500 mg orally twice a day with meals.
• Metformin-containing drugs may be safely used in patients with mild to moderate renal impairment. Renal function should be assessed before starting treatment and at least yearly.
• Metformin should not be used by patients with an estimated glomerular filtration rate (eGFR) below 30 mL/minute/1.73 m2 and starting metformin in patients with an eGFR between 30-45 mL/minute/1.73 m2 is not recommended.
• Metformin should be stopped at the time of or before administering iodinated contrast in patients with an eGFR between 30 and 60 mL/minute/1.73 m2; in patients with a history of liver disease, alcoholism, or heart failure; or in patients who will be administered intra-arterial iodinated contrast.
• Kidney function should be evaluated 48 hours after receiving contrast and metformin may be restarted if kidney function is stable.
• The safety and efficacy of Glucovance has not been established in pediatric patients. Therefore, use of Glucovance in this patient population is not recommended.

• Drugs that cause blood glucose levels to increase may diminish the effectiveness of Glucovance therapy. When these drugs are stopped, patients should be closely observed for signs of low blood glucose. These drugs include
  • thiazides,
  • other diuretics,
  • corticosteroids,
  • phenothiazines,
  • thyroid medications,
  • estrogens,
  • birth control pills,
  • phenytoin (Dilantin),
  • nicotinic acid,
  • sympathomimetics,
  • calcium channel blockers (CCBs), and
  • isoniazid (Nydrazid).
• Cimetidine (Tagamet), by decreasing the elimination of metformin from the body, can increase the amount of metformin in the blood by 40%. This may increase the frequency of side effects from metformin.
• Contrast media used for radiological procedures may reduce kidney function which reduces elimination of metformin, leading to increased concentrations of metformin in the blood. Metformin should be stopped 48 hours before and after use of contrast media.
• Alcohol consumption increases the effect of metformin on lactate production, increasing the risk of lactic acidosis.
• Certain drugs may increase the blood glucose lowering actions of glyburide. It is possible that hypoglycemia (low blood glucose) and symptoms from hypoglycemia may result. Such drugs include
  • nonsteroidal anti-inflammatory medications (NSAIDs),
  • salicylates,
  • sulfonamides,
  • chloramphenicol,
  • probenecid,
  • coumarins,
  • ciprofloxacin (Cipro),
  • monoamine oxidase inhibitors (MAOIs),
  • oral miconazole, and
  • beta-adrenergic blockers.
• Coadministration of glyburide with bosentan (Tracleer) may cause an abnormal increase in liver enzymes. Therefore, concomitant use of these agents is not recommended.
• Colesevelam (Welchol) may reduce blood levels of glyburide. Patients are advised to take glyburide 1 hour before or 4 hours after colesevelam administration to minimize the risk of their interaction.

• Glucovance has not been adequately evaluated in pregnant women. Due to the lack of conclusive safety data, Glucovance should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus. Glucovance is classified as FDA pregnancy risk category B.
• It is not known if Glucovance is excreted in breast milk. Due to the lack of safety data and the potential risk for hypoglycemia (low blood glucose) in nursing infants, use of Glucovance in nursing mothers is not recommended.

What preparations of glyburide/metformin tablets are available?

Oral tablets: 1.25/250, 2.5/500, and 5/500 mg

How should I keep glyburide/metformin tablets stored?

• Tablets should be stored at room temperature, between 15 C and 30 C (59 F to 86 F).
• Tablets should be dispensed and stored in an air- tight, light resistance container.