Rofecoxib

rofecoxib (roh fah cox' hib) Vioxx Pregnancy Category C Drug classes

NSAID Analgesic Selective COX-2 enzyme blocker Therapeutic actions

Analgesic and anti-inflammatory activities related to inhibition of COX-2 enzyme, which is activated in inflammation to cause the signs and symptoms associated with inflammation; does not effect the COX-1 enzyme, which protects the lining of the GI tract and has blood clotting and renal functions. Indications

• • •

Relief of signs and symptoms of osteoarthritis and rheumatoid arthritis Management of acute pain in adults Treatment of primary dysmenorrhea

Contraindications and cautions

• •

Contraindicated with allergy to celecoxib, salicylates or other NSAIDs (more common in patients with rhinitis, asthma, chronic urticaria, nasal polyps), or any component of the drug; renal impairment, lactation. Use cautiously with impaired hepatic or CV function, pregnancy.

Available forms

Tablets—12.5, 25, 50 mg; suspension—12.5 mg/5 mL, 25 mg/5 mL Dosages ADULTS

• • •

Osteoarthritis: 12.5 mg PO daily; do not exceed 25 mg/day. Rheumatoid arthritis: 25 mg PO daily. Primary dysmenorrhea and acute pain: 50 mg PO daily. Do not use > 5 days.

PEDIATRIC PATIENTS

Safety and efficacy not established. Pharmacokinetics Route Oral

Onset 45 min

Peak 2–3 hr

Metabolism: Hepatic; T1/2: 17 hr Distribution: Crosses placenta; may enter breast milk Excretion: Urine and feces

Adverse effects

• • • • •

CNS: Headache, dizziness, somnolence, insomnia, fatigue, tiredness, dizziness, tinnitus, ophthamological effects Dermatologic: Rash, pruritus, sweating, dry mucous membranes, stomatitis Hematologic: Bleeding, leukopenia, pancytopenia, thrombocytopenia, agranulocytosis, granulocytopenia, decreased hemoglobin or hematocrit, bone marrow depression, menorrhagia Respiratory: Dyspnea, hemoptysis, pharyngitis, bronchospasm, rhinitis Other: Peripheral edema, anaphylactoid reactions to fatal anaphylactic shock

Interactions

Drug-drug • Increased risk of bleeding with warfarin; monitor patient closely • Possible increased risk of lithium toxicity; monitor serum levels and adjust dosage appropriately Nursing considerations CLINICAL ALERT!

Name confusion has occurred between Vioxx (rofecoxib) and Zyvox (linezolid); use caution. Assessment

• •

History: Allergy to celecoxib, salicylates or other NSAIDs, or any component of the drug; renal impairment, pregnancy, lactation, impaired hepatic or CV function Physical: Skin color, lesions; T; orientation, reflexes, audiometric evaluation, peripheral sensation; P, BP, edema; R, adventitious sounds; liver evaluation, CBC, clotting times, liver function tests

Interventions

• • • • •

Administer drug with food or after meals if GI upset occurs. Establish safety measures if CNS, visual disturbances occur. Arrange for periodic ophthalmologic examination during long-term therapy. If overdose occurs, institute emergency procedures—gastric lavage, induction of emesis, supportive therapy. Provide further comfort measures to reduce pain (positioning, environmental control) and inflammation (warmth, positioning, rest).

Teaching points

• • • •

Take the drug with food or after meals if GI upset occurs. Do not exceed the prescribed dosage. These side effects may occur: Drowsiness, dizziness, vertigo, insomnia (use caution when driving or operating dangerous machinery if these occur). Report sore throat, fever, rash, itching, weight gain, swelling in ankles or fingers, changes in vision.

Adverse effects in Italic are most common; those in Bold are life-threatening.