Paediatric anaphylaxis — MRCEM SBA MCQ

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EasyPaediatric emergenciesPaediatric anaphylaxisMRCEM SBA

A 7-year-old boy develops widespread urticaria, wheeze and dizziness within minutes of eating a biscuit containing peanuts. In the emergency department he receives 300 micrograms of intramuscular adrenaline. Senior help has been called, high-flow oxygen is being given, and an intravenous crystalloid bolus has started. Five minutes after the adrenaline injection, he remains wheezy and pale, with a blood pressure of 72/40 mmHg. He is conscious and has a palpable pulse. Which drug treatment should be given now?

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Correct answer: A — Repeat intramuscular adrenaline.

The rapid onset of urticaria after peanut exposure, together with wheeze and circulatory compromise, indicates anaphylaxis. His breathing and circulation problems persist five minutes after one appropriate intramuscular adrenaline dose, so the next drug treatment is a second intramuscular dose. Oxygen, crystalloid and senior assessment should continue alongside it. The UK paediatric guidance recommends repeating intramuscular adrenaline at five-minute intervals according to response. ([cats.nhs.uk](https://cats.nhs.uk/wp-content/uploads/cats_anaphylaxis_2026.pdf)) An intravenous adrenaline infusion (B) is a specialist treatment for refractory anaphylaxis when breathing or circulation problems persist despite two appropriate intramuscular doses; he has received one. Nebulised salbutamol (C) may help bronchospasm but does not treat the associated circulatory failure or replace adrenaline. Intravenous hydrocortisone (D) does not provide the immediate treatment needed for persistent breathing and circulation problems. Oral cetirizine (E) may be considered for persisting skin symptoms after stabilisation, but antihistamines do not treat the life-threatening features present here. ([cats.nhs.uk](https://cats.nhs.uk/wp-content/uploads/cats_anaphylaxis_2026.pdf))

Reference: Children’s Acute Transport Service: Anaphylaxis (Active 2026) — https://cats.nhs.uk/wp-content/uploads/cats_anaphylaxis_2026.pdf Anaphylaxis in Adults and Children Clinical Guideline (December 2025) — https://doclibrary-rcht.cornwall.nhs.uk/DocumentsLibrary/RoyalCornwallHospitalsTrust/Clinical/CorporateClinical/AnaphylaxisInAdultsAndChildrenClinicalGuideline.pdf