When a person suffers from allergies, certain allergens can trigger a reaction and cause swelling in the body. While most of the time, these conditions are not life-threatening, there are instances when the throat swells up so much that it restricts the airflow to the lungs while chemicals responsible for attacking the allergen flood the system resulting in blood pressure drop and waker heart rate. This condition or allergic reaction is known as Anaphylaxis and the person undergoes an anaphylactic shock. People who suffer from severe allergies, especially allergies related to food and animal hair, are at greater risk of suffering from anaphylaxis. When the person suffers from an anaphylactic shock, administration of an epinephrine shot is necessary to prevent the person from collapsing.