interferon alpha-2b

interferon alpha-2b

Intron A

Indications

Action

Pharmacokinetics

Time/action profile (clinical effects)

Contraindications/Precautions

Adverse Reactions/Side Effects

Central nervous system

• neuropsychiatric disorders (life-threatening)
• confusion (most frequent)
• depression (most frequent)
• dizziness (most frequent)
• fatigue (most frequent)
• headache (most frequent)
• insomnia (most frequent)
• irritability (most frequent)
• anxiety

Ear, Eye, Nose, Throat

• blurred vision
• nose bleeds (most frequent)
• rhinitis (most frequent)

Cardiovascular

• ischemic disorders (life-threatening)
• arrhythmias
• chest pain
• edema (most frequent)

Gastrointestinal

• colitis (life-threatening)
• pancreatitis (life-threatening)
• anorexia (most frequent)
• abdominal pain (most frequent)
• diarrhea (most frequent)
• dry mouth (most frequent)
• nausea (most frequent)
• taste disorder (most frequent)
• vomiting (most frequent)
• weight loss (most frequent)
• drug-induced hepatitis
• flatulence

Dermatologic

• alopecia (most frequent)
• dry skin (most frequent)
• pruritus (most frequent)
• rash (most frequent)
• sweating (most frequent)

Endocrinologic

• thyroid disorders

Hematologic

• leukopenia
• thrombocytopenia
• anemia (most frequent)
• hemolytic anemia (with ribavirin) (most frequent)

Musculoskeletal

• arthralgia (most frequent)
• myalgia (most frequent)
• leg cramps

Neurologic

• paresthesia

Respiratory

• cough (most frequent)
• dyspnea (most frequent)

Local

• injection site reactions

Miscellaneous

• autoimmune disorders (life-threatening)
• infectious disorders (life-threatening)
• allergic reactions including anaphylaxis (life-threatening)
• chills (most frequent)
• fever (most frequent)
• flu-like syndrome (most frequent)

Interactions

Drug-Drug interaction

Route/Dosage

Availability

Nursing implications

Nursing assessment

• Assess for signs of neuropsychiatric disorders (irritability, anxiety, depression, suicidal ideation, aggressive behavior). May require discontinuation of therapy.
  • Monitor for signs of infection (vital signs, WBC) during therapy. Discontinue drug therapy in cases of severe infection, and antibiotic therapy instituted.
  • Assess for cardiovascular disorders (pulse, BP, chest pain). An ECG should be performed before and periodically during the course of therapy in patients with a history of cardiovascular disease.
  • Assess for signs of colitis (abdominal pain, bloody diarrhea, fever) and pancreatitis (nausea, vomiting, abdominal pain) during therapy. Discontinue therapy if these occur; may be fatal. Colitis usually resolves within 1–3 wk of discontinuation.
  • Assess for development of flu-like syndrome (fever, chills, myalgia, headache). Symptoms often appear suddenly 3–6 hr after therapy. Symptoms tend to decrease, even with continued therapy. Acetaminophen may be used for control of these symptoms.
  • Monitor for bone marrow depression. Assess for bleeding (bleeding gums; bruising; petechiae; guaiac stools, urine, and emesis) and avoid IM injections and rectal temperatures if platelet count is low. Apply pressure to venipuncture sites for 10 min. Assess for signs of infection during neutropenia. Anemia may occur. Monitor for increased fatigue, dyspnea, and orthostatic hypotension.
  • May cause nausea and vomiting. Antiemetics may be used prophylactically. Monitor intake and output, daily weight, and appetite. Adjust diet as tolerated for anorexia. Encourage fluid intake of at least 2 liters/day.
  • Assess pulmonary status (lung sounds, respirations) periodically during therapy.
  • Perform a baseline eye exam in all patients prior to initiation of therapy. Eye exams should be performed periodically during therapy in patients with pre-existing diabetic or hypertensive retinopathy. Discontinue therapy if patients develop new or worsening eye disorders.
  • Assess for signs of thyroid dysfunction, as hypothyroidism or hyperthyroidism may occur. Discontinue therapy if the patient's thyroid function cannot be controlled with medications (e.g., thyroid hormone supplementation, antithyroid medications).
• Kaposi’s Sarcoma: Monitor number, size, and character of lesions prior to and throughout therapy.
• Lab Test Considerations: Systemic: Monitor for CBC and differential prior to and periodically during therapy. May cause leukopenia, neutropenia, thrombocytopenia, decreased hemoglobin and hematocrit, and hemolytic anemia. The nadirs of leukopenia and thrombocytopenia occur in 3–5 days, with recovery 3–5 days after withdrawal of interferon alpha-2b For malignant melanoma, if granulocyte count >250/mm³ but <500/mm³, discontinue interferon alpha-2b until platelet or granulocyte counts return to normal or baseline levels, then reinstitute at 50% of dose. If granulocyte count <250/mm³ with interferon alpha-2b, discontinue permanently. For follicular non-Hodgkin's lymphoma, if granulocyte count <1000/mm³ or platelet count <50,000/mm³, discontinue interferon alpha-2b.
  • Monitor TSH at baseline and if patients develop symptoms consistent with hypothyroidism or hyperthyroidism.
  • Hairy Cell Leukemia: Monitor number of peripheral blood hairy cells and bone marrow hairy cells prior to and during therapy.

Potential Nursing Diagnoses

Implementation

• Solution should be prepared in a biologic cabinet. Wear gloves, gown, and mask while handling medication. Discard equipment in specially designated containers (see ).
• Intramuscular: Subcutaneous: Subcut route is preferred for patients with a platelet count <50,000/mm³.
  • Reconstitute 10-, 18-, and 50-million-unit vials with 1 mL of diluent provided by manufacturer (sterile water for injection). Agitate gently. Solution may be colorless to light yellow. Solution should be used immediately; stable for up to 24 hr if refrigerated.
  • The solution for injection vials do not require reconstitution prior to use and may be used for IM, subcut, or intralesional administration.
  • The solution for injection in multidose pens are for subcut use only. Only the needles provided in the package should be used with the pen. A new needle should be used with each dose. Follow instructions in Medication Guide for use of multidose pens.
• Intralesional: Reconstitute 10-million-unit vial with 1 mL of diluent provided by manufacturer (sterile water for injection). Use a TB syringe with 25–30-gauge needle to administer. Each 0.1-mL dose is injected into the center of the base of the wart using the intradermal injection approach. As many as 5 lesions can be treated at one time.

• Intravenous Administration

• Intermittent Infusion: (For Malignant Melanoma). Diluent: Add 1 mL of diluent provided by manufacturer (sterile water for injection) to vial. Further dilute appropriate dose in 100 mL of 0.9% NaCl. Solution should be used immediately; stable for 24 hr if refrigerated. The solution for injection vials are not recommended for IV administration. Concentration: Not less than 10 million units/100 mL.
• Rate: Infuse over 20 min.

Patient/Family Teaching

• Advise patient to take medication as directed. If a dose is missed, omit dose and return to the regular schedule. Notify health care professional if more than 1 dose is missed.
• Home Care Issues: Instruct patient and family on preparation and correct technique for administration of injection and care and disposal of equipment. Advise patient to read Medication Guide prior to administration and with each prescription refill to check for changes. Explain to patient that brands should not be switched without consulting health care professional; may result in a change of dose.
  • Discuss possibility of flu-like reaction 3–6 hr after dose. Acetaminophen may be taken prior to injection and every 3–4 hr afterward as needed to control symptoms.
  • Review side effects with patient. Interferon may be temporarily discontinued or dose decreased by 50% if serious side effects occur.
  • Instruct patient to notify health care professional promptly if fever; chills; cough; hoarseness; sore throat; signs of infection; lower back or side pain; painful or difficult urination; bleeding gums; bruising; petechiae; blood in stools, urine, or emesis; increased fatigue; dyspnea; or orthostatic hypotension occurs. Caution patient to avoid crowds and persons with known infections. Instruct patient to use soft toothbrush and electric razor and to avoid falls. Caution patient not to drink alcoholic beverages or take medication containing aspirin or NSAIDs; may precipitate gastric bleeding.
  • Inform patient of the potential for depression and advise patient to notify health care professional if depression occurs.
  • Discuss with patient the possibility of hair loss. Explore coping strategies.
  • Explain to patient that fertility may be impaired and that contraception is needed during treatment to prevent potential harm to the fetus.
  • Instruct patient not to receive any vaccinations without advice of health care professional.
  • Emphasize need for periodic lab tests to monitor for side effects.

Evaluation/Desired Outcomes

• Normalized blood parameters (hemoglobin, neutrophils, platelets, monocytes, and bone marrow and peripheral hairy cells) in hairy cell leukemia. Response may not be seen for 6 mo with interferon alpha-2b.
• Decrease in the size and number of lesions in Kaposi’s sarcoma. Therapy may be required for 6 mo before full response is seen. Therapy is continued until disease progresses or a maximum response has been achieved after 4 mo of therapy.
• Increase in time to relapse and overall survival in patients with malignant melanoma.
• Disappearance of or decrease in size and number of genital warts. Condylomata acuminata usually respond in 4–8 wk. A second course of therapy may be required if genital warts persist and laboratory values remain in acceptable limits.
• Decrease in symptoms and improvement in liver function tests and ↓ progression of hepatic damage in patients with hepatitis B or hepatitis C infection.