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Corticosteroid (Antiemetic) Pregnancy: Compatible for perioperative use at standard doses; causes neonatal adrenal suppression at high doses/prolonged use

Dexamethasone (PONV Prevention)

Brand names: Dexamethasone (generic)

Adult dose

Dose: PONV prevention: 4–8 mg IV at induction. Raised ICP: 4–8 mg IV then 4 mg every 6h. Anti-inflammatory: 0.4–20 mg/day
Route: IV
Frequency: Single dose PONV; every 6h for ICP/inflammation
Max: 8 mg for single PONV dose; higher for anti-inflammatory/neurological
At 4 mg IV, equivalent PONV prophylaxis to ondansetron 4 mg. Combination more effective (Apfel score ≥2: consider both). Single 4–8 mg dose does not meaningfully affect blood glucose.

Paediatric dose

Dose: 0.15 mg/kg
Route: IV
Frequency: Single dose (PONV); every 6h (raised ICP)
Max: 8 mg
Concentration: 3.3 mg/mL or 4 mg/mL mg/ml
PONV prophylaxis children: 0.15 mg/kg IV (max 8 mg). Croup: 0.15–0.3 mg/kg single dose (max 10 mg). Raised ICP: 0.5 mg/kg loading then 0.25 mg/kg every 6h.

Dose adjustments

Renal

No dose adjustment required

Hepatic

No dose adjustment required

Paediatric weight-based calculator

PONV prophylaxis children: 0.15 mg/kg IV (max 8 mg). Croup: 0.15–0.3 mg/kg single dose (max 10 mg). Raised ICP: 0.5 mg/kg loading then 0.25 mg/kg every 6h.

Clinical pearls

  • Single perioperative dose: effective, well-tolerated, inexpensive — highly cost-effective PONV prophylaxis
  • Hyperglycaemia: expect 2–4 mmol/L rise in blood glucose after 8 mg dexamethasone — warn diabetic patients, adjust insulin accordingly
  • Apfel score ≥2: combination dexamethasone + 5-HT3 antagonist recommended
  • Dexamethasone administration timing: at induction (for max 6–8h benefit)

Contraindications

  • Systemic infection without antibiotic cover
  • Live vaccines

Side effects

  • Hyperglycaemia (monitor diabetic patients post-operatively)
  • Facial flushing
  • Insomnia
  • Hiccups (single IV dose)
  • Perineal tingling on rapid injection

Interactions

  • NSAIDs — additive GI bleeding risk
  • Anticoagulants — variable effect (monitor)

Monitoring

  • Blood glucose (diabetics)
  • PONV response
  • Surgical wound (if prolonged courses — impaired healing)

Reference: BNFc; BNF; Apfel CC et al PONV Risk Score; SAMBA PONV Guidelines 2020. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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