ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Adrenaline (Epinephrine) — Sympathomimetic Pregnancy: Use in anaphylaxis — no contraindication; risk of untreated anaphylaxis far greater than fetal risk

Adrenaline IM (Paediatric — Anaphylaxis)

Brand names: EpiPen Jr (150 mcg), Jext 150 mcg, Emerade 150 mcg

Adult dose

Dose: Anaphylaxis: 500 mcg (0.5 mL of 1:1000) IM, anterolateral thigh
Route: IM
Frequency: Repeat after 5 min if no improvement
Max: 500 mcg per dose
Adults: see emergency section for full dosing

Paediatric dose

Dose: 10 mcg/kg
Route: IM, anterolateral thigh
Frequency: Repeat after 5 min if no improvement
Max: 500 mcg
Concentration: 1000 mcg/mL (1:1000) — draw up from ampoule or use auto-injector mcg/ml
BNF for Children: 10 mcg/kg IM (max 500 mcg). Auto-injector guide: <15 kg: 150 mcg (EpiPen Jr/Jext 150); 15–30 kg: 300 mcg (EpiPen/Jext 300); >30 kg: 500 mcg drawn up. Anterolateral thigh. Source: BNF for Children 2024; Resuscitation Council UK Anaphylaxis 2021

Dose adjustments

Renal

N/A — emergency medication

Hepatic

N/A — emergency medication

Paediatric weight-based calculator

BNF for Children: 10 mcg/kg IM (max 500 mcg). Auto-injector guide: <15 kg: 150 mcg (EpiPen Jr/Jext 150); 15–30 kg: 300 mcg (EpiPen/Jext 300); >30 kg: 500 mcg drawn up. Anterolateral thigh. Source: BNF for Children 2024; Resuscitation Council UK Anaphylaxis 2021

Clinical pearls

  • IM anterolateral thigh: faster and more reliable absorption than SC or deltoid routes
  • ALWAYS use anterolateral thigh — most accessible site and fastest peak plasma level
  • Prescribe auto-injectors upon discharge after anaphylaxis: write specific auto-injector by brand and dose (EpiPen/Jext/Emerade are NOT bioequivalent — different needle lengths)
  • Refer to allergy specialist after all anaphylaxis episodes — investigation and long-term management plan

Contraindications

  • No absolute contraindications in anaphylaxis — life-threatening

Side effects

  • Tachycardia
  • Palpitations
  • Pallor
  • Anxiety/tremor
  • Hypertension
  • Headache

Interactions

  • Beta-blockers — may reduce effect and cause paradoxical bradycardia
  • MAOIs — potentiated hypertensive response
  • Tricyclic antidepressants — enhanced pressor response

Monitoring

  • Heart rate
  • Blood pressure
  • Respiratory status
  • Skin changes (resolution of urticaria/angioedema)

Reference: BNF for Children; Resuscitation Council UK Anaphylaxis Guidelines 2021; BSACI. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways