Drug Guide
Canagliflozin; Metformin Hydrochloride
Classification
Therapeutic: Antidiabetic agent
Pharmacological: Combination of SGLT2 inhibitor and Biguanide
FDA Approved Indications
- Type 2 diabetes mellitus in adults to improve glycemic control
Mechanism of Action
Canagliflozin inhibits sodium-glucose co-transporter 2 (SGLT2) in the proximal renal tubules, reducing glucose reabsorption and increasing urinary glucose excretion. Metformin decreases hepatic glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity by increasing peripheral glucose uptake and utilization.
Dosage and Administration
Adult: As directed by a healthcare provider, typically once daily with meals. Dose adjustments based on renal function.
Pediatric: Not generally approved for pediatric use.
Geriatric: Use with caution due to potential renal impairment.
Renal Impairment: Adjust dose or avoid based on renal function (eGFR levels).
Hepatic Impairment: Use with caution; contraindicated in severe hepatic impairment.
Pharmacokinetics
Absorption: Both drugs are orally absorbed.
Distribution: Metformin is distributed widely; Canagliflozin binds to plasma proteins.
Metabolism: Metformin is not metabolized appreciably; Canagliflozin is metabolized via glucuronidation.
Excretion: Metformin is excreted unchanged in urine; Canagliflozin is excreted via urine and feces.
Half Life: Metformin: ~6.2 hours; Canagliflozin: ~10-13 hours.
Contraindications
- Severe renal impairment (eGFR <30 mL/min),
- Metabolic acidosis, including diabetic ketoacidosis
Precautions
- Risk of lactic acidosis with metformin,
- Potential dehydration with canagliflozin,
- Monitor renal function periodically.
Adverse Reactions - Common
- Genital mycotic infections (Common)
- Urinary tract infections (Common)
- Nausea and vomiting (Common)
Adverse Reactions - Serious
- Lactic acidosis (Rare)
- Dehydration and hypotension (Rare)
- Ketoacidosis (Rare)
Drug-Drug Interactions
- Other antihyperglycemics, especially insulin and insulin secretagogues (risk of hypoglycemia)
- Diuretics (may increase risk of dehydration)
- ACE inhibitors, ARBs (monitor renal function)
Drug-Food Interactions
- Alcohol (can potentiate lactic acidosis with metformin)
Drug-Herb Interactions
N/ANursing Implications
Assessment: Monitor blood glucose, renal function, signs of dehydration, and urinary tract infections.
Diagnoses:
- Risk for hypoglycemia
- Risk for dehydration
- Impaired skin integrity (genital infections)
Implementation: Administer with meals, monitor renal function regularly, educate patient on signs of adverse effects.
Evaluation: Assess glycemic control and for adverse effects; adjust therapy accordingly.
Patient/Family Teaching
- Take medication with meals to reduce gastrointestinal side effects.
- Stay hydrated and report symptoms of dehydration.
- Practice good genital hygiene to prevent infections.
- Report signs of lactic acidosis (weakness, fatigue, unusual somnolence).
Special Considerations
Black Box Warnings:
- Lactic acidosis with metformin, especially in renal impairment
Genetic Factors: None specified.
Lab Test Interference: May influence blood glucose and renal function tests.
Overdose Management
Signs/Symptoms: Hypoglycemia, lactic acidosis (metformin), dehydration, hypotension.
Treatment: Discontinue medication, provide supportive care, manage hypoglycemia if present, and initiate hemodialysis in severe cases of metformin overdose.
Storage and Handling
Storage: Store at room temperature, away from moisture and heat.
Stability: Stable for the duration of the labeled expiration date.