The most severe allergic reaction is called anaphylaxis. This is a sudden, severe allergic reaction. Signs of anaphylaxis include difficulty breathing, swelling, rapid drop in blood pressure, dizziness, unconsciousness, tightness of the throat and hoarse voice. Anaphylaxis is life-threatening and needs IMMEDIATE treatment. Severe allergies are not curable but can be treated if diagnosed correctly.
Attribution: Straight Talk Foundation