Duration of observation following anaphylaxis; reproduced with permission from the 2021 Resuscitation Council UK guideline, Emergency treatment of anaphylaxis: Guidelines for healthcare providers1
| Consider fast-track discharge (after 2 hours observation from resolution of anaphylaxis) if all or the following: | A minimum of 6 hours observation after resolution of symptoms recommended if: | Observation for at least 12 hours following resolution of symptoms if any one of the following: |
|---|---|---|
| Good response (within 10–15 minutes) to a single dose of adrenaline given within 30 minutes of onset of reaction. and Complete resolution of symptoms. and The patient already has unused adrenaline auto-injectors (AAI) and has been trained how to use them. and There is adequate supervision following discharge. | Two doses of IM adrenaline needed to treat reaction.a or Previous biphasic reaction. | Severe reaction requiring >2 doses of adrenaline. or Patient has severe asthma or reaction involved severe respiratory compromise. or Possibility of continuing absorption of allergen eg slow-release medicines. or Patient presents late at night or may not be able to respond to any deterioration. or Patients in areas where access to emergency care is difficult. |
In all cases, discharge must comply with National Institute for Health and Care Excellence clinical guidance CG134.54
↵aIt may be reasonable for some patients to be discharged after 2 hours, eg following a supervised allergy challenge in a specialist allergy setting. IM = intramuscular.