Nurses Compass
Drug Guide
Peginterferon Alfa-2b
Classification
Therapeutic: Immunomodulator, Antineoplastic agent
Pharmacological: Interferon (Type I)
FDA Approved Indications
- Hairy Cell Leukemia
- Melanoma (adjuvant therapy)
- Chronic Hepatitis B (off-label)
- Chronic Hepatitis C (off-label)
Mechanism of Action
Peginterferon Alfa-2b modulates the immune system by inducing antiviral proteins, inhibiting tumor cell proliferation, and enhancing the immune response against infected or malignant cells.
Dosage and Administration
Adult: Dose varies depending on indication; typically 180 mcg subcutaneously once weekly for hepatitis, adjusted based on response and tolerability.
Pediatric: Use depends on specific condition; consult detailed guidelines.
Geriatric: Use with caution; monitor for enhanced side effects.
Renal Impairment: Adjust dosing based on renal function; specifics depend on condition.
Hepatic Impairment: Use with caution; no specific dose adjustment provided, but monitor closely.
Pharmacokinetics
Absorption: Subcutaneous administration with peak serum levels in 24-48 hours.
Distribution: Widely distributed; high protein binding.
Metabolism: Metabolized via proteolytic enzymes to smaller peptides and amino acids.
Excretion: Primarily via renal route; dosage adjustments may be necessary in renal impairment.
Half Life: Approximately 4.7 hours.
Contraindications
- Hypersensitivity to peginterferon alfa-2b or any component.
- Autoimmune hepatitis.
- Decompensated liver disease.
Precautions
- History of autoimmune disease, psychiatric disorders, cardiac disease.
- Monitoring for flu-like symptoms, depression, hematologic abnormalities is essential.
- Pregnancy category C; use only if clearly needed; effective contraception advised during treatment and for some time after.
Adverse Reactions - Common
- Flu-like symptoms (Very common)
- Fatigue (Very common)
- Myelosuppression (neutropenia, thrombocytopenia, anemia) (Common)
- Injection site reactions (Common)
Adverse Reactions - Serious
- Psychiatric symptoms (depression, suicidal ideation) (Uncommon)
- Hepatotoxicity (liver failure) (Rare)
- Autoimmune disorders (Rare)
Drug-Drug Interactions
- Other myelosuppressants, hepatotoxic drugs, immunosuppressants
Drug-Food Interactions
- No significant interactions reported
Drug-Herb Interactions
- Limited data; caution advised with immune-modulating herbs.
Nursing Implications
Assessment: Monitor CBC, LFTs, and mental status regularly.
Diagnoses:
- Risk for infection, risk for bleeding, risk for impaired skin integrity, altered nutrition.
Implementation: Administer as prescribed subcutaneously; educate patient on signs of adverse effects.
Evaluation: Assess for efficacy (viral load reduction, tumor response) and adverse reactions.
Patient/Family Teaching
- Report flu-like symptoms, mood changes, signs of infection or bleeding promptly.
- Adherence to schedule is critical.
- Avoid live vaccines during therapy.
Special Considerations
Black Box Warnings:
- Neuropsychiatric disorders, autoimmune disorders, ischemic events, and infectious disorders have been noted.
Genetic Factors: No specific genetic considerations specified.
Lab Test Interference: May elevate liver enzymes, affect blood counts.
Overdose Management
Signs/Symptoms: Flu-like symptoms, hematologic abnormalities, neuropsychiatric symptoms.
Treatment: Supportive care, supportive medications for symptoms, and monitoring; no specific antidote.
Storage and Handling
Storage: Store unopened vials refrigerated at 2°C to 8°C (36°F to 46°F). Protect from light.
Stability: Stable until the expiration date printed on the package.