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Non-Selective NSAID (Non-Opioid Analgesic) Pregnancy: Avoid from 20 weeks (renal effects — oligohydramnios); absolute contraindication third trimester

Ibuprofen (Multimodal Post-Operative Analgesia)

Brand names: Nurofen, Brufen

Adult dose

Dose: 400 mg three times daily with or after food
Route: Oral
Frequency: Three times daily (every 8 hours) with food
Max: 2.4 g/day (1.2 g/day in elderly or renal impairment)
Part of multimodal post-operative analgesia (paracetamol + NSAID + weak opioid ± regional anaesthesia). Regular use reduces opioid requirements by 30–50%. Use lowest effective dose for shortest duration. Prescribe PPI (omeprazole 20 mg OD) if at risk of GI side effects.

Paediatric dose

Dose: 5 mg/kg
Route: Oral or IV (ibuprofen lysine)
Frequency: Every 6–8 hours
Max: 30 mg/kg/day (max 2.4 g/day)
Concentration: 100 mg/5 mL (suspension); 200 mg tablet mg/ml
Children ≥3 months: 5–10 mg/kg every 6–8h. Ibuprofen IV (Caldolor): 10 mg/kg every 6h in children ≥6 months. Avoid in children with chickenpox (Reye's syndrome risk with some NSAIDs — debate, but caution advised).

Dose adjustments

Renal

Avoid in eGFR <30 (risk of acute kidney injury); caution in eGFR 30–60

Hepatic

Avoid in severe hepatic impairment

Paediatric weight-based calculator

Children ≥3 months: 5–10 mg/kg every 6–8h. Ibuprofen IV (Caldolor): 10 mg/kg every 6h in children ≥6 months. Avoid in children with chickenpox (Reye's syndrome risk with some NSAIDs — debate, but caution advised).

Clinical pearls

  • Multimodal analgesia cornerstone: ibuprofen + paracetamol regularly = equivalent or superior analgesia to a weak opioid with fewer side effects (constipation, nausea)
  • GI protection: prescribe omeprazole (or lansoprazole) with ibuprofen if risk factors present (age >60, steroids, prior GI bleed, H. pylori)
  • Post-surgical AKI risk: ensure adequate hydration before and during NSAID use; avoid in hypovolaemia
  • Aspirin-exacerbated respiratory disease (NSAID-sensitive asthma): NSAIDs cause bronchoconstriction — use paracetamol + opioid alternative
  • Platelet function: ibuprofen transiently inhibits platelets — consider stopping 5–7 days pre-surgery if platelet function critical (neurosurgery, cardiac)

Contraindications

  • Active peptic ulcer or GI bleed
  • Severe renal impairment (eGFR <30)
  • Severe hepatic impairment
  • Aspirin-exacerbated respiratory disease
  • 3rd trimester of pregnancy
  • Post-CABG (NSAIDs increase MI risk post-cardiac surgery)

Side effects

  • GI upset, nausea, dyspepsia (prescribe PPI if at risk)
  • Peptic ulcer / GI bleed
  • Acute kidney injury (especially in dehydrated, elderly, or renally impaired)
  • Fluid retention and hypertension
  • Bronchospasm (aspirin-sensitive asthma)
  • Platelet inhibition (bleeding risk)

Interactions

  • Anticoagulants — increased bleeding risk
  • ACE inhibitors/ARBs — acute kidney injury triad (hypotension + NSAID + RAAS blockade)
  • Lithium — increased lithium levels
  • Methotrexate — increased toxicity

Monitoring

  • Renal function (U&E — especially in elderly or dehydrated)
  • GI symptoms (dyspepsia, melaena)
  • Blood pressure
  • Hydration status

Reference: BNFc; BNF; NICE NG59 Medicines Optimisation; WHO Analgesic Ladder; SIGN 136 Postoperative Analgesia. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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