When a person has an allergy, he or she experiences an immune response to a substance that is usually not harmful. An allergy emergency may occur if a person is exposed to this allergen. An allergic reaction may become severe if not treated in a timely manner.
People may be allergic to a variety of different things such as:
Anaphylaxis:
This is a severe, life-threatening allergic reaction. It occurs suddenly, and within seconds or minutes after contact with the allergen.
A reaction of troubled breathing can cause obstructions in the airway and even lead to shock. Anaphylaxis requires immediate medical treatment, including the pinephrine injection and a trip to the hospital.