Nurses Compass
Drug Guide
Metformin Hydrochloride and Glipizide
Classification
Therapeutic: Antidiabetic agent (for type 2 diabetes)
Pharmacological: Combination sulfonylurea and biguanide
FDA Approved Indications
- Management of type 2 diabetes mellitus to improve glycemic control.
Mechanism of Action
Metformin decreases hepatic glucose production and increases insulin sensitivity; Glipizide stimulates insulin secretion from pancreatic beta cells.
Dosage and Administration
Adult: Dosage varies based on patient response; initial doses typically are 2.5 mg glipizide with 500 mg metformin once daily, titrated as needed.
Pediatric: Not approved for pediatric use.
Geriatric: Use with caution, monitor renal function closely.
Renal Impairment: Adjust dose based on renal function; contraindicated in severe renal impairment.
Hepatic Impairment: Use with caution; monitor hepatic function.
Pharmacokinetics
Absorption: Metformin is well absorbed; Glipizide is rapidly absorbed.
Distribution: Metformin is minimally bound to plasma proteins; Glipizide is highly protein-bound.
Metabolism: Metformin is not metabolized; Glipizide undergoes hepatic metabolism.
Excretion: Metformin is excreted unchanged in urine; Glipizide metabolites are excreted renally.
Half Life: Metformin: approximately 17.6 hours; Glipizide: about 2-4 hours.
Contraindications
- Severe renal impairment (eGFR <30 mL/min).
- Acute or chronic metabolic acidosis, including diabetic ketoacidosis.
Precautions
- Use cautiously in hepatic impairment, heart failure, and elderly; monitor renal function regularly.
Adverse Reactions - Common
- Nausea (Common)
- Diarrhea (Common)
- Hypoglycemia (Less common when used alone; more with combination therapy.)
Adverse Reactions - Serious
- Lactic acidosis (Rare but serious; risk increased in renal impairment)
Drug-Drug Interactions
- Cimetidine, drugs that impair renal function, corticosteroids, certain diuretics, other hypoglycemics.
Drug-Food Interactions
N/ADrug-Herb Interactions
- Potential interactions with herbal products that affect blood glucose (e.g., ginseng).
Nursing Implications
Assessment: Monitor blood glucose levels, renal function, liver function, and signs of hypoglycemia or lactic acidosis.
Diagnoses:
- Risk for unstable blood glucose levels
- Risk for hypoglycemia
- Risk for lactic acidosis.
Implementation: Administer with meals to reduce gastrointestinal side effects; monitor blood glucose regularly; adjust dose based on response and lab results.
Evaluation: Assess glycemic control and adverse effects; adjust therapy accordingly.
Patient/Family Teaching
- Take medication as prescribed, with meals to minimize gastrointestinal effects.
- Recognize signs of hypoglycemia (sweating, dizziness) and hyperglycemia.
- Maintain regular blood glucose monitoring.
- Report symptoms of lactic acidosis (muscle pain, abnormal fatigue).
Special Considerations
Black Box Warnings:
- Lactic acidosis - increased risk in patients with renal impairment.
- Renal function should be monitored regularly.
Genetic Factors: Consider genetic variability in drug response.
Lab Test Interference: May interfere with certain urine glucose tests.
Overdose Management
Signs/Symptoms: Severe hypoglycemia, lactic acidosis (e.g., hyperventilation, confusion).
Treatment: Immediate administration of glucose; hold the medication; supportive care; dialysis in severe cases.
Storage and Handling
Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F).
Stability: Stable for standard shelf life as per manufacturer instructions.