Naproxen

This topic will discuss naproxen dosing, indications, adverse effects, and more.
Abdelwahab Ward, BS Pharm, PharmD
Analgesic, NSAID (nonopioid), anti-inflammatory and antirheumaticapproved as an over-the-counter (OTC) medication in 1994. For further information, see topic on Recommendations for safety use of NSAIDs. 
Mechanism of Action ã…¡ Naproxen blocks arachidonate binding to competitively inhibit both cyclooxygenase (COX) isoenzymes, COX-1 and COX-2, resulting in analgesic and anti-inflammatory effects.

  • Treatment of acute gout, ankylosing spondylitis, bursitis.
  • Polyarticular juvenile idiopathic arthritis, osteoarthritis, tendonitis, rheumatoid arthritis,
  • Pain, and primary dysmenorrhea.
  • It is considered first-line treatment for acute gouty arthritis, osteoarthritis, musculoskeletal pain, inflammation, and dysmenorrhea.
  • Off-label uses of Naproxen include the treatment of acute migraines and migraine prophylaxis.
  • Mild to moderate arthritis (osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis): 220 to 550 mg PO every 12 hours, taken with food if GI upset occurs (Max: 1650 mg daily for up to 6 months).
  • Acute gouty arthritis: 825 mg PO once, followed by 275 mg PO every 8 hours until symptom resolution, taken with food if GI upset occurs.
  • Acute severe headache or migraine: 550 mg every 12 hours; can increase the dosage to 825 mg PO if needed; do not exceed the max of 1375 mg daily. Naproxen sodium has a longer half-life compared to other NSAID options, but headache relief rates at 2 hours after initial treatment are lower compared to ibuprofen.
  • Maximum recommended daily doses for children 12 years and older: 20 mg/kg/day by mouth, not to exceed 1000 mg/day by mouth; for non-prescription use, 660 mg/day by mouth.
  • Maximum recommended daily doses for children 2 to 12 years: 20 mg/kg/day by mouth, not to exceed 1000 mg/day by mouth. Non-prescription use is not recommended.
  • Maximum recommended daily doses for children less than 2 years: safety and efficacy remain not established.
  • Patients with hepatic impairment: caution is advised with respect to dosing; utilize the lowest recommended dosing regimen initially.
  • Patients with renal impairment: (1) If creatinine clearance (CrCl) is greater than or equal to 30 mL/minute, no dosage adjustment is needed. (2) Naproxen is not recommended for patients with CrCl less than 30 mL/min.
  • Hypersensitivity to NSAID medications.
  • Aspirin or NSAID-induced asthma.
  • Pregnancy (caution against use in 1st trimester, absolute contraindication at 30 weeks gestation).
  • Perioperative use for coronary artery bypass graft surgery (CABG).
  • Route: Oral
  • Peak: 1–4 hours
  • Duration: 8–12 hours
  • Metabolism: Hepatic; T1/2: 12–17 hr
  • Distribution: Highly protein bind (99%); may enter breast milk (Naproxen anion has been found in the milk of lactating women at a concentration equivalent to approximately 1% of maximum Naproxen concentration in plasma)
  • Excretion: Urine (95%)
  • Gastrointestinal effects include gastrointestinal intolerance and peptic ulcer disease (Erosive Gastritis). For further information, see topic on Peptic ulcer, assessment and management.
  • Renal effects. Prostaglandins produced by both COX-1 and COX-2 are important regulators of renal function, hemodynamics, and sodium and water reabsorption in the kidneys. When renal blood flow is dependent upon prostaglandin synthesis, NSAID administration can result in significant decreases in renal blood flow, leading to acute kidney injury and renal failure. Also, alterations in sodium and water reabsorption may increase blood pressure, especially in patients with pre-existing hypertension.
  • Bleeding risk (inhibits platelet aggregation)
  • Naproxen (Naprosyn) increases risk almost as much as aspirin
Abdelwahab Ward, BS Pharm, PharmD