Home Drug Guide Rituximab

Drug Guide

Generic Name

Rituximab

Brand Names Rituxan

Classification

Therapeutic: Antineoplastic and Immunomodulating Agent

Pharmacological: Monoclonal Antibody

FDA Approved Indications

  • Non-Hodgkin's lymphoma
  • Chronic lymphocytic leukemia
  • Rheumatoid arthritis (with methotrexate)
  • Granulomatosis with polyangiitis (GPA)
  • Microscopic polyangiitis

Mechanism of Action

Rituximab is a chimeric monoclonal antibody targeting CD20 antigen on B-cells, leading to B-cell depletion via complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, and apoptosis.

Dosage and Administration

Adult: Varies based on indication; typically 375 mg/m² weekly for 4 weeks for lymphoma, 1000 mg on days 1 and 15 for rheumatoid arthritis.

Pediatric: Use in pediatric populations is limited and based on specific indications and protocols.

Geriatric: No specific dosage adjustments, but monitor for increased risk of adverse effects in older adults.

Renal Impairment: No specific dose adjustment required.

Hepatic Impairment: Limited data; use with caution.

Pharmacokinetics

Absorption: Administered IV; bioavailability not applicable.

Distribution: Widely distributed in the body, including B-cells in lymphoid tissues.

Metabolism: Degraded via proteolytic catabolism into peptides and amino acids.

Excretion: Cleared through reticuloendothelial system; not primarily renal.

Half Life: Approximately 3-4 days, varies with dose and treatment schedule.

Contraindications

  • Hypersensitivity to Rituximab or its components.

Precautions

  • Increased risk of infections, including reactivation of hepatitis B and progressive multifocal leukoencephalopathy (PML).
  • Monitor for infusion reactions, especially during the first infusion.

Adverse Reactions - Common

  • Infusion reactions (fever, chills, rigors, hypotension) (Common)
  • Upper respiratory tract infections (Common)
  • Fatigue, nausea, cough (Common)

Adverse Reactions - Serious

  • Severe infusion reactions, including bronchospasm, hypotension, angioedema (Uncommon)
  • PML, a fatal brain infection (Rare)
  • Severe neutropenia, thrombocytopenia, or anemia (Uncommon)
  • Hepatitis B reactivation (Rare)

Drug-Drug Interactions

  • Other immunosuppressants, vaccines (live), other biologics

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for infusion reactions, infections, CBC counts, liver function tests.

Diagnoses:

  • Risk for infection related to immunosuppression.
  • Risk for allergic reaction related to infusion.

Implementation: Pre-medicate with acetaminophen, antihistamines, and corticosteroids to reduce infusion reactions.

Evaluation: Assess for signs of infection, review blood counts, monitor infusion site reactions.

Patient/Family Teaching

  • Report any signs of infection immediately.
  • Understand the importance of follow-up blood tests.
  • Be aware of potential infusion reactions and how they are managed.

Special Considerations

Black Box Warnings:

  • Progressive multifocal leukoencephalopathy (PML), a rare brain infection, can be fatal.
  • Hepatitis B reactivation, which can be severe or fatal.

Genetic Factors: Screen for hepatitis B surface antigen and core antibody before initiating therapy.

Lab Test Interference: May cause falsely low values in certain immunoassays.

Overdose Management

Signs/Symptoms: Unknown, but potential for severe infusion reactions or immune suppression.

Treatment: Supportive care; no specific antidote.

Storage and Handling

Storage: Refrigerate between 2°C and 8°C, protected from light.

Stability: Stable until 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.