Naproxen Data - Uses, Dosage, Drug class, Brand name, Warnings, etc

Pharmacology	Naproxen is an NSAID with analgesic and antipyretic properties. It is a nonselective inhibitor of cyclo-oxygenase-1 (COX-1) and cyclo-oxygenase-2 (COX-2) and reversibly alters platelet function and prolongs bleeding time.
Administration and Adult Dosage	- PO for mild to moderate pain, dysmenorrhea, or acute tendinitis or bursitis: • Naproxen: 500 mg initially, followed by 250 mg every 6–8 hr, to a maximum of 1250 mg/day • Naproxen sodium: 550 mg initially, followed by 275 mg every 6–8 hr, to a maximum of 1375 mg/day - PO for rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis: • Naproxen: 250–500 mg twice daily initially, to a maximum of 1500 mg/day for limited periods • Naproxen sodium: 275–550 mg twice daily or 275 mg every morning and 550 mg every evening initially, to a maximum of 1650 mg/day for limited periods • If no improvement after 4 weeks, consider other drug therapy - PO for acute gout: • Naproxen: 750 mg initially, followed by 250 mg every 8 hr until resolved • Naproxen sodium: 825 mg initially, followed by 275 mg every 8 hr until resolved
Special Populations - Pediatric Dosage	- PO for juvenile arthritis: 10 mg/kg/day in 2 divided doses
Special Populations - Geriatric Dosage	Use minimal effective dosages; elderly are more susceptible to GI bleeding and acute renal insufficiency.
Dosage Forms	- Tablet (naproxen): 250, 375, 500 mg - Tablet (naproxen sodium): 220, 275, 550 mg - Enteric-Coated Tablet (naproxen): 375, 500 mg - Sustained-Release Tablet (naproxen sodium): 375, 500, 750 mg - Suspension (naproxen): 25 mg/mL
Patient Instructions	- Take with food, milk, or antacid to minimize stomach upset - Report symptoms of gastrointestinal ulceration or bleeding, skin rash, weight gain, or edema - Dizziness may occur; use caution until the extent of this effect is known
Missed Doses	- If taken on a regular schedule, take a missed dose as soon as remembered - If near the time for the next dose, take that dose only; do not double the dose or take extra
Pharmacokinetics - Serum Levels	- Trough concentrations for rheumatoid arthritis: >50 mg/L (>217 µmol/L) associated with response
Pharmacokinetics - Fate	- Absorption: Rapidly absorbed from the GI tract; bioavailability ~99% - Protein Binding: >99.7%, saturable with increasing dosage; increased with uremia, cirrhosis, and in the elderly; decreased in rheumatoid arthritis and hypoalbuminemia - Distribution: Vd = 0.16 ± 0.02 L/kg, increased in uremia, cirrhosis, and rheumatoid arthritis - Clearance: Cl = 0.0078 ± 0.0012 L/hr/kg, increased in rheumatoid arthritis, decreased in uremia - Excretion: <1% unchanged in urine
Pharmacokinetics - t¹⁄₂	- Elimination half-life: 14 ± 1 hr, increased in the elderly
Adverse Reactions & Side Effects	Occasional: - Gastric distress, blood loss, diarrhea, vomiting, dizziness, skin rash - GI ulceration (higher risk in elderly and with higher dosages) - Fluid retention Other: - Renal dysfunction, particularly in pre-existing renal disease, CHF, or cirrhosis - Interstitial nephritis and nephrotic syndrome Rare: - Slight rise in bleeding time, elevated liver enzymes, lymphopenia, agranulocytosis, aplastic anemia, aseptic meningitis
Contraindications	- Syndrome of nasal polyps - Angioedema - Bronchospastic reactivity to aspirin or other NSAIDs
Precautions & Warnings	- Avoid during pregnancy - Use with caution in patients with pre-existing renal disease, CHF, cirrhosis, history of ulcer disease or bleeding, or risk factors for peptic ulcer disease (e.g., advanced age)
Drug Interactions	- May inhibit antihypertensive response to ACE inhibitors, beta-blockers, diuretics, and hydralazine - May inhibit natriuretic effect of diuretics - Possible GI bleeding and antiplatelet effect increase bleeding risk during anticoagulant therapy - May decrease renal lithium clearance - Some NSAIDs (e.g., indomethacin, ketoprofen) reduce methotrexate clearance - May reduce renal function
Parameters to Monitor	- Monitor for blood loss, weight gain, and renal function during long-term use
Class and Drug Brand Name	- Class: Analgesic and Anti-Inflammatory Drugs - Brand Names: Naprosyn (naproxen), Anaprox (naproxen sodium)
Notes	- Misoprostol is effective in preventing NSAID-associated GI ulceration - H2-receptor antagonists prevent duodenal but not gastric ulcerations and may mask symptoms of NSAID-induced GI ulceration - Proton-pump inhibitors (e.g., omeprazole) are effective in treating NSAID-related dyspepsia and preventing NSAID-induced ulcers

References

Hand of Clinical Drug Data