Home Drug Guide Cetuximab

Drug Guide

Generic Name

Cetuximab

Brand Names Erbitux

Classification

Therapeutic: Antineoplastic, Monoclonal Antibody

Pharmacological: EGFR inhibitor

FDA Approved Indications

  • Locally or regionally advanced squamous cell carcinoma of the head and neck
  • METASTATIC colorectal cancer that expresses the epidermal growth factor receptor (EGFR)

Mechanism of Action

Cetuximab is a chimeric monoclonal antibody that binds to the extracellular domain of the epidermal growth factor receptor (EGFR), inhibiting ligand binding and subsequent receptor activation. This inhibits cell proliferation and induces apoptosis in tumor cells overexpressing EGFR.

Dosage and Administration

Adult: Initial dose: 400 mg/m² IV over 120 minutes, followed by weekly infusions of 250 mg/m² over 60 minutes.

Pediatric: Not approved for pediatric use.

Geriatric: No specific dose adjustment required, but caution in elderly patients due to potential for increased toxicity.

Renal Impairment: No specific recommendations, but close monitoring advised.

Hepatic Impairment: No specific data; use caution.

Pharmacokinetics

Absorption: Administered intravenously; bioavailability not applicable.

Distribution: Widely distributed in body tissues.

Metabolism: Metabolized by proteolytic enzymes.

Excretion: Metabolized similar to endogenous immunoglobulins; renal excretion not significant.

Half Life: Approximately 5-8 days.

Contraindications

  • Hypersensitivity to cetuximab or any component of the formulation.

Precautions

  • Use with caution in patients with cardiac disease, pulmonary fibrosis, or active infections. Risk of infusion reactions and skin toxicity. Discontinue if severe infusion reactions occur.

Adverse Reactions - Common

  • Infusion reactions (Approximately 3-5%)
  • Acneiform rash (Common, up to 80%)
  • Fatigue (Common)
  • Mucocutaneous dryness, pruritus (Common)

Adverse Reactions - Serious

  • Anaphylaxis (Rare)
  • Cardiac arrest (rare) (Very rare)
  • Severe skin reactions, interstitial lung disease (rare) (Rare)

Drug-Drug Interactions

  • Chemotherapy agents such as cisplatin, fluorouracil, irinotecan may increase toxicity.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for infusion reactions, skin toxicity, signs of cardiopulmonary issues.

Diagnoses:

  • Risk for infusion reaction
  • Impaired skin integrity

Implementation: Premedicate with antihistamines or corticosteroids as appropriate. Monitor skin and patient response.

Evaluation: Assess for adverse reactions, effectiveness of tumor response, and skin changes.

Patient/Family Teaching

  • Report any infusion reactions such as difficulty breathing, swelling, or rash.
  • Use sun protection to minimize skin reactions.
  • Report new or worsening symptoms immediately.

Special Considerations

Black Box Warnings:

  • Serious infusion reactions may occur, including fatal reactions.
  • Cardiac arrest has occurred rarely.

Genetic Factors: KRAS mutation status may guide use in colorectal cancer; only use in KRAS wild-type tumors.

Lab Test Interference: EGFR expression testing required for some indications.

Overdose Management

Signs/Symptoms: Hypersensitivity reactions, cardiac arrhythmias, skin reactions.

Treatment: Discontinue infusion; provide supportive care; no specific antidote.

Storage and Handling

Storage: Store refrigerated at 2-8°C.

Stability: Stable until the expiration date on the vial.

🛡️ 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.