Table 1

Factors to be considered as part of the risk assessment on whether to prescribe epinephrine autoinjectors

	UK (BSACI)48	Europe (EAACI)10	Australia (ASCIA)17	Evidence
Previous history	Anaphylaxis and at risk of ongoing exposure Mild reaction to ‘trace’ amount of allergen History of cofactors (eg, exercise) impacting on reaction severity	Anaphylaxis Mild reaction to ‘trace’ amount of allergen Venom allergy in adults with systemic symptoms	Anaphylaxis and at ongoing risk of exposure Generalised urticaria alone without anaphylaxis due to insect sting in adults	Previous anaphylaxis indicates potential for future reactions, although risk of fatal anaphylaxis remains low.7 15 No evidence that individuals who react to very low amounts of allergen are more likely to experience severe anaphylaxis.9 Children with local or generalised skin rashes only to venom are at very low risk of anaphylaxis with subsequent stings.10 48
Allergen-specific risk factors	High-risk allergens, for example, nuts Allergen difficult to avoid	High-risk allergens, for example, nuts	High-risk allergens, for example, nuts, seafood	In the UK, cow’s milk and peanut/tree nuts are the most common cause of fatal anaphylaxis.2
Patient-specific risk factors	Teenage/young adults Food allergy* to high-risk allergens (eg, nuts) and other risk factors (eg, asthma) Raised baseline serum tryptase Limited access to emergency medical care, for example, remote location, social factors	Teenager or young adult with a food allergy* Food allergy* and coexisting unstable or moderate–severe, persistent asthma Underlying mast cell disorders or raised baseline serum tryptase Remote from medical help	Teenagers and young adults with food allergy Food allergy* and coexisting unstable or moderate–severe, persistent asthma Underlying mast cell disorders (eg, systemic mastocytosis or raised baseline serum tryptase) Limited access to emergency medical care, for example, remote location, foreign travel Cardiovascular disease	Data suggests a specific vulnerability to severe outcomes from food-induced allergic reactions in teenagers and young adults.2 9 Poor asthma control increases risk of severe reactions; most cases of fatal food-induced anaphylaxis have asthma, but asthma itself is poorly predictive of severe outcomes as it is so prevalent in food-allergic individuals.9 Underlying mast cell disorders are a known risk factor for venom and idiopathic anaphylaxis.10 17 48 Remote access to medical support causes delays in emergency treatment.

Factors in bold are specified as ‘absolute’ (EAACI) or ‘recommended’ (ASCIA) indications.
*Excluding pollen food allergy syndrome.
ASCIA, Australasian Society of Clinical Immunology and Allergy; BSACI, British Society for Allergy and Clinical Immunology; EAACI, European Academy of Allergy and Clinical Immunology.