Metformin Hydrochloride / Glibenclamide

What it is and how it works

Mechanism of Action Glyburide primarily lowers blood glucose by stimulating the release of insulin from the pancreas, an effect dependent upon functioning beta cells in the pancreatic islets. Sulfonylureas bind to the sulfonylurea receptor in the pancreatic beta-cell plasma membrane, leading to closure of the ATP-sensitive potassium channel, thereby stimulating the release of insulin. Metformin is an antihyperglycemic agent that improves glucose tolerance in patients with type 2 diabetes, lowering both basal and postprandial plasma glucose.

Indications

Glyburide and metformin hydrochloride tablets are indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. Glyburide and metformin hydrochloride tablets are a combination of glyburide, a sulfonylurea, and metformin hydrochloride (HCl), a biguanide, indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.

Dosage and administration (summary)

Adult Dosage: Give glyburide and metformin hydrochloride tablets in divided doses, twice daily, with meals. For patients not treated with either glyburide (or another sulfonylurea) or metformin HCl, initiate treatment with another formulation with a dose of 1.25 mg glyburide and 250 mg metformin HCl orally, once or twice daily with meals. For patients not adequately controlled on either glyburide (or another sulfonylurea) or metformin HCl alone, the recommended starting dose is 2.5 mg/500 mg or 5 mg/500 mg orally twice daily with meals.

Contraindications

Glyburide and metformin hydrochloride tablets are contraindicated in patients with: Severe renal impairment (eGFR below 30 mL/min/1.73 m 2 ) . Hypersensitivity to metformin or glyburide. Acute or chronic metabolic acidosis, including diabetic ketoacidosis, with or without coma. Concomitant administration of bosentan . Severe renal impairment (eGFR below 30 mL/min/1.73 m 2 ) ( 4 , 5.1 ) Hypersensitivity to metformin or glyburide.

Warnings and precautions

Lactic Acidosis: See boxed warning. Hypoglycemia: May be severe. Ensure proper patient selection, dosing, and instructions, particularly in at-risk populations (e.g., elderly, renally impaired) and when used with other anti-diabetic medications. Potential Increased Risk of Cardiovascular Mortality with Sulfonylureas: Inform patient of risks, benefits and treatment alternatives. Hemolytic anemia: Can occur if glucose 6-phosphate dehydrogenase (G6PD) deficient. Consider a non-sulfonylurea alternative. Vitamin B 12 Deficiency: Metformin may lower vitamin B 12 levels.

Pregnancy

Pregnancy Risk Summary Available data from a small number of published studies and postmarketing experience with glyburide use in pregnancy over decades have not identified any drug associated risks for major birth defects, miscarriage, or adverse maternal outcomes.

Storage and supply

Glyburide and metformin hydrochloride tablets, USP are available as follows: Glyburide and metformin hydrochloride tablets, 1.25 mg/250 mg are white to off-white colored, capsule shaped, biconvex coated tablets, debossed with "653" on one side and plain on the other side and are supplied as follows: NDC 68382-653-06 in bottles of 30 tablets NDC 683…

Source: Glyburide And Metformin Hydrochloride (Glyburide And Metformin Hydrochloride) — US FDA prescribing information, 2026-06-10, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.