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Non-selective NSAID Pregnancy: Avoid in third trimester (ductus arteriosus). Use for shortest time in second trimester only if essential.

Naproxen

Brand names: Naprosyn, Napratec, Naproxen EC

Adult dose

Dose: 250–500 mg twice daily; acute gout: 750 mg then 250 mg every 8 hours
Route: Oral
Frequency: Twice daily
Max: 1.25 g/day
RA/OA/AS: 500 mg BD. Acute gout: 750 mg initially then 250 mg every 8 hours until attack resolves (max 1.25 g/day). Acute musculoskeletal: 500 mg initially then 250 mg TDS. Always prescribe PPI (omeprazole 20 mg) with NSAID. Avoid in cardiovascular disease, renal impairment, elderly.

Paediatric dose

Dose: 5 mg/kg
Route: Oral
Frequency: Twice daily
Max: 500 mg/dose
≥5 years (JIA): 10 mg/kg/day in 2 divided doses (max 500 mg BD). Take with food or milk.

Dose adjustments

Renal

Avoid if eGFR <30. Use with caution eGFR 30–60. Risk of acute kidney injury.

Hepatic

Use with caution in mild-moderate hepatic impairment. Avoid in severe.

Paediatric weight-based calculator

≥5 years (JIA): 10 mg/kg/day in 2 divided doses (max 500 mg BD). Take with food or milk.

Clinical pearls

  • Co-prescribe PPI (e.g., omeprazole 20 mg) for all patients taking NSAIDs regularly
  • 'Triple whammy': NSAID + ACE inhibitor/ARB + diuretic — high AKI risk in elderly — avoid this combination
  • Naproxen has better cardiovascular safety profile vs diclofenac and rofecoxib
  • Use lowest effective dose for shortest duration in OA/RA
  • Acute gout: faster onset than allopurinol — use for acute attacks while initiating ULT

Contraindications

  • Active peptic ulcer / GI bleeding
  • Severe heart failure
  • Severe renal impairment (eGFR <30)
  • Aspirin-exacerbated respiratory disease
  • Pregnancy (third trimester — premature closure of ductus arteriosus)

Side effects

  • GI upset, peptic ulceration, GI bleeding
  • Fluid retention and oedema
  • Hypertension (sodium retention)
  • Renal impairment (acute or chronic)
  • Hypersensitivity reactions
  • Cardiovascular events (less than diclofenac; similar to ibuprofen)

Interactions

  • Warfarin — increased bleeding risk (both GI and INR effects)
  • Lithium — increases lithium levels
  • Methotrexate — reduces MTX excretion (caution)
  • Antihypertensives — reduced efficacy (NSAIDs raise BP)
  • ACE inhibitors/ARBs — triple whammy with diuretics (AKI risk)

Monitoring

  • U&E and creatinine (especially in elderly/renal risk)
  • BP
  • GI symptoms
  • FBC (long-term)

Reference: BNFc; BNF; NICE NG100 RA; NICE NG219 Gout; MHRA NSAIDs prescribing guidance. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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