8 July 2025
Adrenaline auto-injectors for acute anaphylaxis
We recently undertook a review of dosing of adrenaline/epinephrine auto-injector devices for acute anaphylaxis (for self-administration at the first signs of anaphylaxis); this followed feedback from prescribers about the difference in recommendations between Jext® and Epipen® for the body-weight at which children transition from 150 micrograms to 300 micrograms auto-injectors. Previously, dose recommendations in BNF and BNFC were in line with the licence: for Jext®, children transition from 150 micrograms to 300 micrograms at a body-weight of 30 kg; however, for EpiPen®, a dose of 300 micrograms is recommended from 25 kg. Our review found that guidelines from the British Society for Allergy and Clinical Immunology (BSACI), the European Academy of Allergy and Clinical Immunology (EAACI), and from other countries that have a similar healthcare system structure to the UK, such as the USA and Canada, supported dose transition to 300 micrograms at a body weight of 25 kg. Consequently, the body-weight ranges for Jext® have been aligned with those of EpiPen® so that all children with body-weight 25 kg and over may be given a dose of 300 micrograms. An unlicensed use statement in the adrenaline/epinephrine monograph highlights that dosing given via an auto-injector for acute anaphylaxis may differ from the licence.
Updated dosing can be seen in the Adrenaline/Epinephrine monograph; this update was published in December 2024 for online and in-app versions of BNF and BNFC. It was published in print for BNF 89 (March – September 2025) and will be included in BNF for Children 2025-2026. This change was subject to our clinical governance process which involves input from our expert clinical advisory group, as well as ratification by our Paediatric Formulary Committee, to ensure changes are robust and in line with the best available evidence. Further information on our clinical governance committees.
