Anaphylaxis is a serious allergic reaction. It begins suddenly. it may cause death. Anaphylaxis has many symptoms (signs of being sick), such as an itchy rash, throat swelling, breathing problems, and low blood pressure. Common causes include insect bites, foods, and medications.
Anaphylaxis happens when a person eats, breathes in, or is injected with an allergen (something they are allergic to). Their immune system over-reacts. It sends out special proteins from inside certain white blood cells. These proteins can start an allergic reaction or make the reaction worse.
Anaphylaxis is diagnosed (found to be sick with something) from a person’s signs and symptoms. The best treatment is an injection (a shot) of epinephrine (adrenaline). Sometimes doctors give other medicines along with epinephrine.
Worldwide, about 0.05–2% of people have anaphylaxis at some point in their lives. Anaphylaxis appears to be getting more common.