Naproxen

Indications

Naproxen is used for: Rheumatoid arthritis, Ankylosing spondylitis, Post-operative pain, Dysmenorrhea, Acute gout, Acute migraine attacks, Renal colic, Mild to moderate pain, Tendonitis, Osteoarthritis (degenerative arthritis), Acute musculoskeletal disorders, Bursitis

Adult Dose

Adults Oral: Pain 500 mg PO initially, then 250 mg PO q6-8hr or 500 mg PO q12hr PRN; not to exceed 1250 mg/day naproxen base on day 1; subsequent daily doses should not exceed 1000 mg naproxen base Extended release: 750-1000 mg PO qDay; may temporarily increase to 1500 mg/day if tolerated well and clinically indicated Rheumatoid Arthritis, Osteoarthritis, Ankylosing Spondylitis 500-1000 mg/day PO divided q12hr; may increase to 1500 mg/day if tolerated well for limited time Extended release: 750-1000 mg PO qDay; may temporarily increase to 1500 mg/day if tolerated well and clinically indicated Dysmenorrhea 500 mg PO initially, then 250 mg PO q6-8hr or 500 mg PO q12hr (long-acting formula); not to exceed 1250 mg/day on first day; subsequent doses should not exceed 1000 mg/day naproxen base Gout, Acute 750 mg PO initially, followed by 250 mg q8hr until attack subsides Extended release: 1000-1500 mg qDay, followed by 1000 mg qDay until attack subsides

Child Dose

Pain >12 years 500 mg PO initially, then 250 mg PO q6-8hr or 500 mg PO q12hr PRN; not to exceed 1250 mg/day naproxen base on day 1; subsequent daily doses should not exceed 1000 mg naproxen base Extended release: 750-1000 mg PO qDay; may temporarily increase to 1500 mg/day if tolerated well and clinically indicated Juvenile Idiopathic Arthritis >2 years: 10 mg/kg/day oral suspension PO divided q12hr; not to exceed 15 mg/kg/day

Renal Dose

Renal impairment: CrCl <30 mL/min: Use not recommended Severe: Contraindicated.

Administration

Should be taken with food.

Contra Indications

Hypersensitivity. Aspirin or NSAID allergy. Perioperative pain in the setting of CABG surgery. Pregnancy (3rd trimester).

Precautions

Patient w/ known CV disease or risk factors for CV disease, history of GI bleeding or peptic ulceration, fluid retention or heart failure. Hepatic and renal impairment. Elderly. Pregnancy and lactation. Patient Counselling May impair ability to drive and operate machinery. Monitoring Parameters BP should be monitored closely during initiation and throughout therapy. Perform periodically renal function, CBC and chemistry profile in patients receiving long-term therapy. Lactation: Drug excreted in breast milk; effect on infant unknown; not recommended

Pregnancy-Lactation

Pregnancy There are no adequate and well-controlled studies in pregnant women; data from observational studies regarding potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive; NSAIDs inhibit prostaglandin synthesis, cause delayed parturition, and increase the incidence of stillbirth Lactation The naproxen anion has been found in the milk of lactating women at a concentration equivalent to approximately 1% of maximum naproxen concentration in plasma; developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for therapy and any potential adverse effects on breastfed infant from therapy or from underlying maternal condition

Interactions

May enhance methotrexate toxicity. Reduced BP response to ACE inhibitors or angiotensin II receptor antagonists. Increased risk of serious GI events (e.g. ulcer) w/ aspirin. Increased risk of GI bleeding w/ warfarin. May reduce the natriuretic effects of furosemide or thiazide diuretics. May increase serum lithium concentrations and reduce renal lithium clearance. Delayed absorption w/ antacids, colestyramine or sucralfate. May interfere w/ the antihypertensive effects of beta-blockers (e.g. propranolol). May increase serum levels w/ probenecid.

Adverse Effects

Side effects of Naproxen : 1-10% Abdominal pain (3-9%), Constipation (3-9%), Dizziness (3-9%), Drowsiness (3-9%), Headache (3-9%), Heartburn (3-9%), Nausea (3-9%), Edema (3-9%), GI bleeding (1-4%), GI perforation (1-4%), Lightneadedness (<3%), GI ulcers (1-4%), Fluid retention (3-9%), Diarrhea (1-3%), Stomatitis (<3%), Diverticulitis (1-3%), Dyspnea (3-9%), Hearing disturbances (<3%) <1% Meaningful (3 × upper limit of normal) elevation of serum alanine aminotransferase or aspartate aminotransferase

Mechanism of Action

Naproxen, a propionic acid derivative, is a prototypical NSAID. It reversibly inhibits the cyclooxygenase-1 and -2 (COX-1 and -2) enzymes, thus resulting in reduced synthesis of prostaglandin precursors. It can inhibit platelet aggregation, has anti-inflammatory, analgesic and antipyretic actions.