Generic Name

Glipizide

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Classification

FDA Approved Indications

• Management of type 2 diabetes mellitus to improve glycemic control

Mechanism of Action

Stimulates insulin release from pancreatic beta cells by binding to sulfonylurea receptors, leading to increased insulin secretion and decreased blood glucose levels.

Dosage and Administration

Adult: Starting dose typically 5 mg once daily before meals; titrate based on response, up to a maximum of 40 mg/day.

Pediatric: Not approved for pediatric use.

Geriatric: Start at lower doses due to increased sensitivity and risk of hypoglycemia.

Renal Impairment: Use with caution; monitor blood glucose closely.

Hepatic Impairment: Use with caution; dose adjustments may be necessary.

Pharmacokinetics

Absorption: Well absorbed after oral administration.

Distribution: Widely distributed; plasma protein binding approximately 98%.

Metabolism: Primarily hepatic metabolism via CYP2C9.

Excretion: Excreted mainly in urine as metabolites.

Half Life: Approximately 2-4 hours (immediate-release); 10-16 hours for extended-release formulation.

Contraindications

• Allergy to sulfonylureas or hypersensitivity to glipizide.
• Type 1 diabetes mellitus.
• Diabetic ketoacidosis.

Precautions

• Risk of hypoglycemia, particularly in elderly, malnourished, or those with hepatic or renal impairment.
• Use cautiously in patients with severely impaired kidney or liver function.

Adverse Reactions - Common

• Hypoglycemia (Common)
• Weight gain (Common)
• Headache (Less common)

Adverse Reactions - Serious

• Severe hypoglycemia (Serious)
• Allergic skin reactions (Less common)
• Hematologic reactions (e.g., leukopenia, aplastic anemia) (Rare)

Drug-Drug Interactions

• Sulfonamides, beta-blockers, corticosteroids, diazoxide, certain fluoroquinolones

Drug-Food Interactions

• Alcohol may potentiate hypoglycemia or hyperglycemia.

Drug-Herb Interactions

N/A

Nursing Implications

Patient/Family Teaching

• Take medication as prescribed, at the same time each day.
• Recognize and manage signs of hypoglycemia (e.g., sweating, confusion, shakiness).
• Maintain a consistent diet and exercise regimen.
• Carry a source of fast-acting carbohydrate.

Special Considerations

Black Box Warnings:

• Risk of severe hypoglycemia, especially in the elderly or with renal impairment.

Genetic Factors: Some variability in response due to CYP2C9 genetic polymorphisms.

Lab Test Interference: May cause false elevation of blood glucose in some glucose testing methods.

Overdose Management

Signs/Symptoms: Severe hypoglycemia—confusion, seizures, coma.

Treatment: Administer oral glucose if conscious; intravenous glucose or glucagon in severe cases.

Storage and Handling

Storage: Store at room temperature away from moisture, heat, and light.

Stability: Stable under recommended conditions.