Home Drug Guide Vandetanib

Drug Guide

Generic Name

Vandetanib

Brand Names Caprelsa

Classification

Therapeutic: Antineoplastic agent (Thyroid cancer)

Pharmacological: Selective inhibitor of VEGFR, EGFR, and RET tyrosine kinases

FDA Approved Indications

  • Medullary thyroid carcinoma (MTC) in patients with unresectable locally advanced or metastatic disease

Mechanism of Action

Vandetanib inhibits the activity of multiple receptor tyrosine kinases, including VEGFR, EGFR, and RET, which are involved in tumor growth and angiogenesis, thereby reducing tumor progression.

Dosage and Administration

Adult: Typically 300 mg orally once daily. Dose adjustments may be needed based on tolerability and side effects.

Pediatric: Not approved for pediatric use.

Geriatric: Use with caution; no specific dose adjustment based on age alone, but monitor closely.

Renal Impairment: No specific adjustment recommended; however, severity of impairment may require dose modifications.

Hepatic Impairment: Use with caution; in severe hepatic impairment, dose adjustment is recommended.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Extensive protein binding (~95%).

Metabolism: Hepatic via CYP3A4 and conjugation pathways.

Excretion: Primarily fecal, minor renal excretion.

Half Life: 40 to 45 days, allowing once-daily dosing.

Contraindications

  • Hypersensitivity to vandetanib or any component of the formulation.

Precautions

  • QT prolongation risk, cardiac arrhythmias, arterial thrombosis, bleeding, gastrointestinal perforation, interstitial lung disease, hepatotoxicity, skin reactions, and interactions with drugs prolonging QT interval. Regular monitoring of cardiac function and electrolytes is recommended. Use in pregnancy and breastfeeding is contraindicated.

Adverse Reactions - Common

  • Diarrhea (Common)
  • QT prolongation (Common)
  • rash (Common)
  • Hypertension (Common)

Adverse Reactions - Serious

  • QT prolongation leading to Torsades de Pointes (Serious but less common)
  • Interstitial lung disease/pneumonitis (Rare)
  • Hepatotoxicity (Rare)
  • Cardiac failure, arrhythmias (Rare)

Drug-Drug Interactions

  • Other QT-prolonging drugs (e.g., amiodarone, sotalol)
  • CYP3A4 inhibitors or inducers

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor ECG for QT prolongation, electrolytes, blood pressure, liver function tests, and pulmonary symptoms.

Diagnoses:

  • Risk for cardiac arrhythmias due to QT prolongation
  • Risk for bleeding
  • Impaired skin integrity

Implementation: Administer as prescribed; monitor labs and vital signs regularly; educate patient on symptoms of adverse effects.

Evaluation: Assess for signs of adverse reactions, effectiveness of therapy, and patient adherence.

Patient/Family Teaching

  • Report symptoms like irregular heartbeat, chest pain, shortness of breath, or severe diarrhea.
  • Attend regular lab and ECG appointments.
  • Avoid other medications that prolong QT interval without physician approval.
  • Use effective contraception during treatment and for at least 4 months after discontinuation.

Special Considerations

Black Box Warnings:

  • QT prolongation and sudden death

Genetic Factors: Patients with inherited long QT syndrome should not use vandetanib.

Lab Test Interference: May cause elevated liver enzymes and electrolyte disturbances.

Overdose Management

Signs/Symptoms: Severe diarrhea, hypotension, arrhythmias, bleeding.

Treatment: Supportive care; observe cardiac and respiratory function; correct electrolytes; ensure adequate hydration.

Storage and Handling

Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F).

Stability: Stable through expiration date when stored properly.

🛡️ 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.