NAPROXEN
(na-prox'en)
Apo-Naproxen

, EC-Naprosyn, Naprelan, Naprosyn, Naxen

, Novonaprox

NAPROXEN SODIUM
Aleve, Anaprox, Anaprox DS
Classifications: central nervous system agent; analgesic; nsaid; antipyretic
Prototype: Ibuprofen
Pregnancy Category: B

Availability

200 mg, 250 mg, 375 mg, 500 mg tablets; 375 mg, 500 mg sustained release tablets

Actions

Propionic acid derivative. NSAID with properties similar to those of other propionic acid derivatives, e.g., ibuprofen, fenoprofen, ketoprofen. Mechanism of action thought to be related to inhibition of prostaglandin synthesis.

Therapeutic Effects

Analgesic, antiinflammatory and antipyretic effects; also inhibits platelet aggregation and prolongs bleeding time but does not alter whole blood clotting, prothrombin time or platelet count. Cross-sensitivity with other NSAIDs has been reported.

Uses

Antiinflammatory and analgesic effects in symptomatic treatment of acute and chronic rheumatoid arthritis, juvenile arthritis (naproxen only), and for treatment of primary dysmenorrhea. Also management of ankylosing spondylitis, osteoarthritis, and gout.

Unlabeled Uses

Paget's disease of bone, Bartter's syndrome.

Contraindications

Active peptic ulcer; patients in whom asthma, rhinitis, urticaria, bronchospasm, or shock is precipitated by aspirin or other NSAIDs. Safety during pregnancy (category B), lactation, or in children <2 y is not established.

Cautious Use

History of upper GI tract disorders; impaired kidney, liver, or cardiac function; patients on sodium restriction (naproxen sodium); low pretreatment Hgb concentration; fluid retention, hypertension, heart failure; older adults.

Route & Dosage

Note: 275 mg naproxen sodium = 250 mg naproxen

Inflammatory Disease
Adult: PO 250–500 mg b.i.d. (max: 1000 mg/d naproxen, 1100 mg/d naproxen sodium); Naprelan is dosed q.d.
Child: PO >2 y, 10–15 mg/kg/d in 2 divided doses (max: 1000 mg/d)

Mild to Moderate Pain, Dysmenorrhea
Adult: PO 500 mg followed by 200–250 mg q6–8h prn up to 1250 mg/d
Child: PO >2 y, 5–7 mg/kg q8–12h

Administration

Oral

Ensure that extended release or enteric-coated form is not chewed or crushed. It must be swallowed whole.
Give with food or an antacid (if prescribed) to reduce incidence of GI upset.
Store at 15°–30° C (59°–86° F) in tightly closed container; protect from freezing.

Adverse Effects (1%)

CNS: Headache, drowsiness, dizziness, lightheadedness, depression. CV: Palpitation, dyspnea, peripheral edema, CHF, tachycardia. Special Senses: Blurred vision, tinnitus, hearing loss. GI: Anorexia, heartburn, indigestion, nausea, vomiting, thirst, GI bleeding, elevated serum ALT, AST. Hematologic: Thrombocytopenia, leukopenia, eosinophilia, inhibited platelet aggregation, agranulocytosis (rare). Skin: Pruritus, rash, ecchymosis. Urogenital: Nephrotoxicity. Respiratory: Pulmonary edema.

Diagnostic Test Interference

Transient elevations in BUN and serum alkaline phosphatase may occur. Naproxen may interfere with some urinary assays of 5-HIAA and may cause falsely high urinary 17-KGS levels (using m-dinitrobenzene reagent). Naproxen should be withdrawn 72 h before adrenal function tests.

Interactions

Drug: Bleeding time effects of oral anticoagulants, heparin may be prolonged; may increase lithium toxicity. Herbal: Feverfew, garlic, ginger, ginkgo may increase bleeding potential.

Pharmacokinetics

Absorption: Almost completely absorbed from GI tract when taken on empty stomach. Peak: 2 h naproxen; 1 h naproxen sodium. Duration: 7 h. Metabolism: Metabolized in liver. Elimination: Excreted primarily in urine; some biliary excretion (<1%). Half-Life: 12–15 h.

Nursing Implications

Assessment & Drug Effects

Take detailed drug history prior to initiation of therapy. Observe for signs of allergic response in those with aspirin or other NSAID sensitivity.
Lab tests: Obtain baseline and periodic evaluations of Hgb and kidney and liver function in patients receiving prolonged or high dose therapy.
Schedule baseline and periodic auditory and ophthalmic examinations in patients receiving prolonged or high dose therapy.
Monitor therapeutic effectiveness. Patients with arthritis may experience symptomatic relief (reduction in joint pain, swelling, stiffness) within 24–48 h with naproxen sodium therapy and in 2–4 wk with naproxen.

Patient & Family Education

Be aware that the therapeutic effect of naproxen may not be experienced for 3–4 wk.
Do not drive or engage in potentially hazardous activities until response to drug is known.
Avoid alcohol and aspirin (as well as other NSAIDs) unless otherwise advised by a physician. Potential to increase risk of GI ulceration and bleeding.
Tell your dentist or surgeon if you are taking naproxen before any treatment; it may prolong bleeding time.
Do not breast feed while taking this drug without consulting physician.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug