What Is Glyburide and How Does It Work?

Glyburide is a diabetes medicine used to help control blood sugar levels and treat type 2 diabetes.

Glyburide is available under the following different brand names: Diabeta, Glynase, and Glynase PresTab.

Dosage of Glyburide

Dosage Forms and Strengths

1.25 mg

2.5 mg

5 mg

Tablet, micronized

1.5 mg

3 mg

5 mg

6 mg

Dosing Consideraations – Should be Given as Follows:

Type 2 Diabetes Mellitus

Regular tablets

Initial: 2.5-5 mg orally once/day

Maintenance: 1.25-20 mg orally once/day or every 12 hours

Not to exceed 20 mg/day

Consider administering every 12 hours for doses greater than 10 mg/day

Micronized tablets

Initial: 1.5-3 mg orally once/day

Maintenance: 0.75-12 mg orally once/day

Not to exceed 12 mg/day

Patients at risk for hypoglycemia: 0.75 mg orally once/day initially

Transferring from insulin therapy to glyburide

Current insulin dose less than 20 units: Discontinue insulin and initiate glyburide dose at 2.5-5 mg/day (regular) or 1.5-3 mg/day (micronized)

Current insulin dose 20-40 units: Discontinue insulin and initiate glyburide dose at 5 mg/day (regular) or 3 mg/day (micronized)

Current insulin dose more than 40 units: Decrease insulin dose by 50% and initiate glyburide dose at 5 mg/day (regular) or 3 mg/day (micronized); increase glyburide dose by 1.25-2.5 mg (regular) or 0.75-1.5 mg/day (micronized); decrease insulin dose gradually, based on patient's response as glyburide dose increased


Initial: 1.25 mg/day if non-micronized tablets or 0.75 mg/day of micronized tablets

Depending on glucose response, may increase dose by no more than 1.25-2.5 mg (regular) or 0.75-1.5 mg (micronized) every week

May administer maintenance dose of 1.25-20 mg/day (regular) or 0.75-12 mg/day (micronized); for better satisfactory response may divide dose every 12 hours for patients taking greater than 10 mg/day (regular) or greater than 6 mg/day (micronized)

Dosage Modifications

Renal impairment: If CrCl less than 50 mL/min; caution advised

Hepatic impairment: Use conservative initial and maintenance doses; avoid use in severe liver disease

Pediatric: Safety and efficacy not established

Dosing considerations, geriatric

Because the elderly are susceptible to the hypoglycemic effects of glucose-lowering drugs, the question of how tightly glucose levels should be controlled is controversial

Recognizing hypoglycemia in the elderly may be challenging

Monitoring other parameters associated with cardiovascular disease, such as blood pressure and cholesterol, may be more important than normalized glycemic control

Initial and maintenance dosing should be conservative

Use caution in patients with renal insufficiency

What Are Side Effects Associated with Using Glyburide?

There are no known side effects of glyburide.

Common side effects of glyburide (Mifeprex) include:

Serious side effects of glyburide include:

  • Stomach pain
  • Low grade fever
  • Loss of appetite
  • Dark urine
  • Clay-colored stools
  • Jaundice (yellowing of the skin or eyes)
  • Pale skin
  • Confusion
  • Weakness
  • Easy bruising or bleeding
  • Purple or red pinpoint spots under your skin
  • Headache
  • Trouble concentrating
  • Memory problems
  • Unsteadiness
  • Hallucinations
  • Fainting
  • Seizures
  • Shallow breathing
  • Breathing that stops

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

What Other Drugs Interact with Glyburide?

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.

Severe Interactions of glyburide include:

  • bosentan

Serious interactions of glyburide include:

  • aminolevulinic acid
  • eluxadoline
  • ethanol
  • fluvastatin
  • ivacaftor
  • lumacaftor/ivacaftor
  • methyl aminolevulinate

Glyburide has moderate interactions with at least 191 different drugs.

Glyburide has mild interactions with at least 108 different drugs.

This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns or for more information about this medicine.

What Are Warnings and Precautions for Glyburide?


This medication contains glyburide. Do not take Diabeta, Glynase, or Glynase PresTab if you are allergic to glyburide or any ingredients contained in this drug.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.


  • Hypersensitivity; sulfa allergy
  • Type 1 diabetes
  • Diabetic ketoacidosis
  • Co-administration with bosentan; increased risk of hepatotoxicity

Short-Term Effects

  • See "What Are Side Effects Associated with Using Glyburide?"

Long-Term Effects

  • See "What Are Side Effects Associated with Using Glyburide?"



  • Patients with risk of severe hypoglycemia: Elderly, debilitated, or malnourished or with adrenal or pituitary insufficiency
  • Patients with stress due to infection, fever, trauma, or surgery
  • Caution in hepatic or renal insufficiency
  • Caution in pregnancy/lactation
  • Administration of oral hypoglycemic drugs has been reported to be associated with increased cardiovascular mortality as compared to treatment with diet alone or diet plus insulin
  • Hemolytic anemia may occur with glucose 6-phosphate dehydrogenase (G6PD) deficiency when treated with sulfonylurea agents
  • There are no clinical studies establishing conclusive evidence of macrovascular risk reduction with anti-diabetic drugs
  • All sulfonylureas are capable of producing severe hypoglycemia.

Pregnancy and Lactation

  • Use with glyburide caution during pregnancy if benefits outweigh risks
  • Animal studies show risk and human studies are not available or neither animal nor human studies were done
  • It is not known if glyburide crosses into breast milk; avoid use in nursing women
Medscape. Glyburide.
RxList. Diabeta Side Effects Center.

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