Enbrel

Action

Reacts with and deactivates free-floating tumor necrosis factor, responsible for inflammation

Availability

Powder for injection: 25 mg in multiple-use vial

Prefilled syringe (single-use): 50 mg/ml

Indications and dosages

➣ Moderately to severely active rheumatoid arthritis; ankylosing spondylitis; psoriatric arthritis

Adults: 50 mg subcutaneously q week given as a single injection. Dosages above 50 mg/week are not recommended.

➣ Chronic moderate to severe plaque psoriasis

Adults ages 18 and older: 50 mg subcutaneously twice weekly (given 3 or 4 days apart) for 3 months, followed by reduction to a maintenance dosage of 50 mg weekly

➣ Polyarticular-course juvenile rheumatoid arthritis

Children ages 4 to 17: 0.8 mg/kg subcutaneously q week, to a maximum of 50 mg weekly

Contraindications

• Hypersensitivity to drug or its components

• Sepsis

Precautions

Use cautiously in:

• immunosuppression, chronic infection, heart failure

• latex allergy (needle cover of diluent syringe contains latex)

• elderly patients

• pregnant or breastfeeding patients

• children younger than age 4.

Administration

• Inject subcutaneously into thigh, abdomen, or upper arm.

• For adult, use single-use, 50 mg/ml prefilled syringe.

• For child weighing 63 kg (138 lb) or more, use single-use, 50 mg/ml pre-filled syringe for weekly dose; for child weighing 31 to 62 kg (68 to 137 lb), administer total weekly dose from multipleuse vial as two injections on same day or 3 or 4 days apart; for child weighing less than 31 kg (68 lb), give as a single weekly injection using multipleuse vial.

• Rotate injection sites.

Adverse reactions

CNS: asthenia, headache, depression, dizziness, paresthesia, fatigue, demyelinating disorders (such as multiple sclerosis and myelitis), cerebral hemorrhage, seizures, cerebrovascular accident (CVA)

CV: hypotension, hypertension, chest pain, deep-vein thrombosis, thrombophlebitis, myocardial ischemia, myocardial infarction (MI), heart failure

EENT: ocular inflammation, pharyngitis, rhinitis, sinusitis

GI: nausea, vomiting, diarrhea, abdominal pain, dyspepsia, anorexia, cholecystitis, abdominal abscess, GI hemorrhage, intestinal perforation, pancreatitis

GU: pyelonephritis, membranous glomerulonephropathy

Hematologic: anemia, aplastic anemia, leukopenia, pancytopenia, thrombocytopenia

Metabolic: hypomagnesemia

Musculoskeletal: bursitis, polymyositis, joint pain

Respiratory: cough, congestion, dyspnea, bronchitis, pneumonia, pulmonary embolism, interstitial lung disease

Skin: flushing, cellulitis, pruritus, rash, cutaneous vasculitis, urticaria, alopecia, angioedema

Other: altered taste, weight gain, adenopathy, fever, irritation at injection site, peripheral edema, flulike symptoms, autoantibody formation, lupus-like syndrome, serious infections, malignancies

Interactions

None significant

Patient monitoring

☞ Watch for signs and symptoms of malignancies, pancytopenia and infection.

☞ Monitor for evidence of GI bleeding, lupus-like syndrome, and serious hypersensitivity reactions. Stop therapy immediately if these occur.

• Monitor CBC and coagulation studies.

☞ Check for signs and symptoms of cardiac compromise and cerebrovascular events.

• Monitor pulmonary function test results periodically to assess lung status.

• Assess patient's ability to self-administer drug.

• Check for irritation at injection site. As needed, apply cool compresses.

• Examine eyes for conjunctival dryness. As needed, apply artificial tears.

Patient teaching

☞ Tell patient to withhold dose and contact prescriber if he develops signs or symptoms of infection or is exposed to anyone with chickenpox.

☞ Tell patient to immediately report hypersensitivity reaction, neurologic or respiratory problems, sudden weight gain, chest pain, or easy bruising or bleeding.

• Teach patient or caregiver how to administer drug and handle and dispose of equipment.

• Caution patient not to get live-virus vaccines.

• Tell female to inform prescriber if she is pregnant or breastfeeding.

• Advise patient to expect redness, swelling, and pain at injection site. Assure him that these problems will diminish over time.

• As appropriate, review all other significant and life-threatening adverse reactions mentioned above.