Home Drug Guide Sitagliptin Phosphate and Metformin Hydrochloride

Drug Guide

Generic Name

Sitagliptin Phosphate and Metformin Hydrochloride

Brand Names Jentadueto

Classification

Therapeutic: Antidiabetic agent, combination; Oral hypoglycemic agent

Pharmacological: Dipeptidyl peptidase-4 (DPP-4) inhibitor and Biguanide

FDA Approved Indications

  • Type 2 diabetes mellitus, as an adjunct to diet and exercise to improve glycemic control

Mechanism of Action

Sitagliptin inhibits DPP-4 enzyme, increasing incretin levels which stimulate insulin release and decrease glucagon levels in a glucose-dependent manner. Metformin decreases hepatic glucose production, increases insulin sensitivity, and enhances peripheral glucose uptake.

Dosage and Administration

Adult: Typically, one tablet twice daily with meals, dosage based on renal function and tolerability.

Pediatric: Not approved for use in pediatric patients.

Geriatric: Adjustments may be necessary based on renal function; initial lower doses recommended.

Renal Impairment: Dose adjustment required; contraindicated in severe impairment.

Hepatic Impairment: Use with caution; contraindicated in severe hepatic disease.

Pharmacokinetics

Absorption: Both drugs are well absorbed, with metformin absorption being incomplete.

Distribution: Metformin distributes into tissues; sitagliptin is mainly in plasma.

Metabolism: Metformin is not metabolized; sitagliptin undergoes minimal metabolism.

Excretion: Primarily excreted unchanged in urine; renal function impacts clearance.

Half Life: Approximately 12 hours for sitagliptin; about 17.6 hours for metformin.

Contraindications

  • Renal impairment (eGFR below 45 mL/min/1.73m²),
  • Metabolic acidosis, including diabetic ketoacidosis

Precautions

  • Monitor renal function regularly, risk of lactic acidosis with metformin, potential for hypoglycemia when combined with other agents.

Adverse Reactions - Common

  • Hypoglycemia (Less common with monotherapy)
  • Gastrointestinal upset (nausea, diarrhea) (Common in initial treatment)

Adverse Reactions - Serious

  • Lactic acidosis (Rare but serious)
  • Pancreatitis (Rare)

Drug-Drug Interactions

  • Insulin and other secretagogues (hypoglycemia risk)
  • Cationic drugs affecting renal function

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood glucose and renal function regularly.

Diagnoses:

  • Risk for unstable blood glucose levels
  • Risk for lactic acidosis

Implementation: Administer with meals to reduce gastrointestinal side effects.

Evaluation: Assess blood glucose control and renal function periodically.

Patient/Family Teaching

  • Take medication as prescribed, especially with meals.
  • Report symptoms of hypoglycemia, lactic acidosis, or pancreatitis.
  • Maintain regular blood glucose and renal function monitoring.

Special Considerations

Black Box Warnings:

  • Lactic acidosis risk with metformin, especially in renal impairment.

Genetic Factors: Not specifically related to genetic factors.

Lab Test Interference: May interfere with serum lactate and blood glucose tests.

Overdose Management

Signs/Symptoms: Severe hypoglycemia, lactic acidosis (metformin overdose).

Treatment: Discontinue medication; supportive care; consider hemodialysis for metformin toxicity.

Storage and Handling

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

Stability: Stable under recommended storage conditions.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.