NSAID Analgesia
Pregnancy: CONTRAINDICATED from 20 weeks gestation — risk of premature ductal closure and fetal renal impairment (FDA 2020)
Ibuprofen
Brand names: Nurofen, Brufen
Adult dose
Dose: 400–600 mg
Route: Oral
Frequency: Every 6–8 hours with food
Max: 2.4 g/24h
Used for dysmenorrhoea, endometriosis-related pain, post-operative gynaecological analgesia. CONTRAINDICATED from 20 weeks gestation onwards due to risk of premature closure of ductus arteriosus and fetal renal impairment.
Paediatric dose
Dose: 5–10 mg/kg mg/kg
Route: Oral
Frequency: Every 6–8 hours
Max: 40 mg/kg/day (max 2.4 g/day)
BNFc: not recommended under 3 months or <5 kg
Dose adjustments
Renal
Avoid if eGFR <30 mL/min/1.73m² — risk of acute kidney injury
Hepatic
Use with caution in moderate hepatic impairment; avoid in severe
Paediatric weight-based calculator
BNFc: not recommended under 3 months or <5 kg
Clinical pearls
- CONTRAINDICATED from 20 weeks gestation — FDA 2020 warning: oligohydramnios and fetal renal dysfunction even with short-term use
- Previously considered safe before 30 weeks; guidance changed in 2020 — avoid from 20 weeks unless no alternative
- Excellent for primary dysmenorrhoea — start 1–2 days before expected menses
- Effective for endometriosis-related pelvic pain as adjunct to hormonal therapy
- MHRA: diclofenac cardiovascular risk equivalent to COX-2 inhibitors (2013) — applies class-wide to NSAIDs
Contraindications
- Pregnancy ≥20 weeks (FDA 2020 warning)
- Active peptic ulcer disease
- Renal impairment
- Aspirin-sensitive asthma
- Breastfeeding not recommended (limited data)
Side effects
- GI bleeding
- Renal impairment
- Fluid retention
- Cardiovascular events
- Premature ductus arteriosus closure (fetal)
Interactions
- Lithium — increased lithium levels
- ACE inhibitors — reduced antihypertensive effect + AKI risk
- Warfarin — increased bleeding risk
- SSRIs — GI bleed risk
Monitoring
- Renal function
- Blood pressure
- GI symptoms
Reference: BNFc; BNF 90; FDA Drug Safety Communication (2020) NSAIDs in pregnancy; MHRA (2013). Verify against your local formulary and the latest BNF before prescribing.
Related
Curated clinical cross-links plus same-class fallbacks.