Context

Anaphylaxis is a severe, life-threatening, generalised or systemic hypersensitivity reaction, characterised by rapidly developing and life threatening airway, breathing and/or circulation problems, usually associated with skin and mucosal changes.

It usually has a rapid onset with multiple organ involvement and is mostly caused by specific antigens in sensitised individuals.

The range of possible presentations can make diagnosis difficult but medical treatment must be started as soon as possible.

A significant number of cases of anaphylaxis are idiopathic [1].