Home Drug Guide Metformin Hydrochloride; Saxagliptin Hydrochloride

Drug Guide

Generic Name

Metformin Hydrochloride; Saxagliptin Hydrochloride

Brand Names Kombiglyze XR, Saxagliptin and Metformin Hydrochloride

Classification

Therapeutic: Antidiabetic combination, Antidiabetic agent

Pharmacological: Biguanide (Metformin), Dipeptidyl peptidase-4 (DPP-4) inhibitor (Saxagliptin)

FDA Approved Indications

Type 2 diabetes mellitus in patients who require combination therapy when diet and exercise are insufficient

Mechanism of Action

Metformin decreases hepatic glucose production and increases insulin sensitivity; Saxagliptin inhibits DPP-4 enzyme, increasing incretin levels which enhance glucose-dependent insulin secretion and decrease glucagon levels.

Dosage and Administration

Adult: Typically, one tablet twice daily with meals. Dose adjustments depend on glycemic response.

Pediatric: Not approved for pediatric use.

Geriatric: Start at lower doses due to increased risk of lactic acidosis and renal impairment; monitor renal function regularly.

Renal Impairment: Use with caution; contraindicated in severe renal impairment (eGFR <30 mL/min). Dose adjustment required.

Hepatic Impairment: Use with caution; no specific dose recommendations but monitor closely.

Pharmacokinetics

Absorption: Metformin: >50% absorbed; Saxagliptin: well absorbed

Distribution: Metformin: minimal plasma protein binding; Saxagliptin: approximately 22% protein bound

Metabolism: Metformin: not metabolized; Saxagliptin: metabolized by CYP3A4/5

Excretion: Metformin: renal excretion; Saxagliptin: renal and fecal excretion

Half Life: Metformin: ~4-8 hours; Saxagliptin: ~2.5 hours

Contraindications

Renal impairment, metabolic acidosis, hypersensitivity to components

Precautions

Renal function should be monitored regularly, especially in elderly or those with comorbidities; risk of lactic acidosis with Metformin.

Adverse Reactions - Common

Gastrointestinal upset (nausea, diarrhea) (Common)
Headache (Common)
Respiratory infections (Common)

Adverse Reactions - Serious

Lactic acidosis (Rare but serious)
Pancreatitis (Uncommon)
Hypoglycemia (mainly with other antidiabetics) (Uncommon)

Drug-Drug Interactions

Cimetidine, alcohol (may increase risk of lactic acidosis with Metformin); CYP3A4 inhibitors (may increase Saxagliptin levels)

Drug-Food Interactions

Alcohol (risk of lactic acidosis)

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood glucose levels, renal function (serum creatinine, eGFR), and signs of hypoglycemia.

Diagnoses:

Risk for hypoglycemia
Risk for lactic acidosis

Implementation: Administer with meals; educate about symptoms of hypoglycemia and lactic acidosis.

Evaluation: Evaluate blood glucose control and adverse effects regularly.

Patient/Family Teaching

Take medication with meals to reduce gastrointestinal side effects.
Report symptoms of hypoglycemia (shaking, sweating, confusion) or lactic acidosis (weakness, hyperventilation, unusual muscle pain).
Maintain hydration and avoid excessive alcohol intake.

Special Considerations

Black Box Warnings:

Lactic acidosis risk with Metformin, especially in patients with renal impairment.

Genetic Factors: No specific genetic factors influencing use.

Lab Test Interference: No significant interference.

Overdose Management

Signs/Symptoms: Lactic acidosis, hypoglycemia (less common for Metformin alone)

Treatment: Supportive care, intravenous bicarbonate for acidosis, hemodialysis in severe cases.

Storage and Handling

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

Stability: Stable for the shelf life stated in packaging.