Nurses Compass
Drug Guide
Glyburide
Classification
Therapeutic: Antidiabetic agent
Pharmacological: Sulfonylurea
FDA Approved Indications
- Management of type 2 diabetes mellitus as an adjunct to diet and exercise
Mechanism of Action
Glyburide stimulates insulin release from pancreatic beta cells by binding to sulfonylurea receptors, thereby increasing insulin secretion and decreasing blood glucose levels.
Dosage and Administration
Adult: Typically, 2.5 to 5 mg once daily before breakfast. Dose may be adjusted based on glycemic response, up to a maximum of 20 mg/day.
Pediatric: Not recommended for use in children.
Geriatric: Initial dose should be low, with careful monitoring due to increased risk of hypoglycemia.
Renal Impairment: Use with caution; may require dose adjustment or discontinuation due to accumulation.
Hepatic Impairment: Use with caution; careful monitoring recommended.
Pharmacokinetics
Absorption: Well absorbed from the gastrointestinal tract.
Distribution: Widely distributed; crosses the placenta.
Metabolism: Metabolized in the liver via oxidation and conjugation.
Excretion: Excreted primarily in feces and urine.
Half Life: 10 hours approximately.
Contraindications
- Known hypersensitivity to glyburide or sulfonylureas.
- Diabetic ketoacidosis.
Precautions
- Use with caution in patients with hepatic or renal impairment, in the elderly, and during pregnancy and lactation. Increased risk of hypoglycemia in these populations.
Adverse Reactions - Common
- Hypoglycemia (Common)
- Gastrointestinal disturbances (nausea, abdominal pain) (Less common)
Adverse Reactions - Serious
- Severe hypoglycemia (Serious)
- Jaundice, hepatotoxicity (Rare)
- Allergic skin reactions (Rare)
Drug-Drug Interactions
- Other antidiabetic agents, especially insulin and meglitinides, increase hypoglycemia risk.
- Macrolide antibiotics (e.g., erythromycin) may enhance hypoglycemic effect.
Drug-Food Interactions
- Alcohol may potentiate hypoglycemia.
Drug-Herb Interactions
- St. John’s Wort may decrease glyburide effectiveness.
Nursing Implications
Assessment: Monitor blood glucose levels regularly. Assess for signs of hypoglycemia.
Diagnoses:
- Risk for unstable blood glucose levels
- Risk for hypoglycemia
Implementation: Administer with breakfast or the first main meal of the day. Educate patient on recognizing and managing hypoglycemia.
Evaluation: Evaluate blood glucose control regularly; adjust dose as needed.
Patient/Family Teaching
- Take medication as prescribed, with meals.
- Recognize signs of hypoglycemia and how to treat it.
- Maintain dietary and activity recommendations.
- Avoid alcohol and excess activity that could cause hypoglycemia.
Special Considerations
Black Box Warnings:
- Risk of severe hypoglycemia, which can be life-threatening.
Genetic Factors: Genetic polymorphisms may affect drug metabolism and response.
Lab Test Interference: May interfere with certain laboratory tests, including blood glucose measurements.
Overdose Management
Signs/Symptoms: Severe hypoglycemia—confusion, seizure, coma.
Treatment: Administer oral glucose if conscious; intramuscular or intravenous glucose for unconscious patients. Seek immediate medical care.
Storage and Handling
Storage: Store at room temperature away from moisture and heat.
Stability: Stable under recommended storage conditions.