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NSAID (Non-Steroidal Anti-Inflammatory Drug) Pregnancy: Avoid in third trimester; use with caution in earlier pregnancy

Naproxen

Brand names: Naprosyn, Feminax Ultra

Adult dose

Dose: 250-500 mg twice daily
Route: Oral
Frequency: Twice daily with food
Max: 1000 mg/day
Lower cardiovascular risk than diclofenac or COX-2 inhibitors — preferred NSAID when one is necessary and cardiovascular risk must be considered

Paediatric dose

Dose: Seek specialist opinion N/A/kg
Route: Oral
Frequency: Seek specialist opinion
Max: Seek specialist opinion
Seek specialist opinion

Dose adjustments

Renal

Avoid in eGFR under 30

Hepatic

Use with caution; avoid in severe hepatic impairment

Paediatric weight-based calculator

Seek specialist opinion

Clinical pearls

  • Among oral NSAIDs, naproxen has the most favourable cardiovascular risk profile — preferred choice when an oral NSAID is unavoidable in elderly with cardiovascular risk factors
  • GI risk remains significant — always co-prescribe PPI (e.g. omeprazole 20 mg) in elderly on NSAIDs
  • Beers Criteria 2023: All oral NSAIDs are potentially inappropriate in elderly — topical NSAIDs preferred for localised pain
  • Twice-daily dosing may improve adherence but increases dosing burden compared to once-daily alternatives
  • NICE CG177 (Gout): NSAIDs (including naproxen) first-line for acute gout in patients without contraindications — use for shortest duration possible

Contraindications

  • Active GI ulceration or bleeding
  • Severe renal or hepatic impairment
  • Heart failure
  • Third trimester of pregnancy

Side effects

  • GI ulceration and bleeding
  • Renal impairment
  • Fluid retention
  • Hypertension
  • Cardiovascular events (lower than diclofenac but not zero risk)

Interactions

  • Warfarin / DOACs (increased bleeding)
  • ACEi / ARBs + diuretics (triple whammy — AKI)
  • Lithium (increases levels)
  • Aspirin (reduces efficacy of aspirin's antiplatelet effect)

Monitoring

  • Renal function
  • Blood pressure
  • GI symptoms
  • Fluid retention

Reference: BNFc; BNF 90; NICE CG177 (Gout); NICE NG226 (Osteoarthritis); AGS Beers Criteria 2023; STOPP/START v3. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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