Allergies occur when the immune system reacts to a foreign substance (such as pollen, bee venom or pet dander) or a food that does not cause a reaction in most people.
Your immune system produces substances known as “antibodies.” When you have allergies, your immune system produces antibodies that identify a particular allergen as harmful, even if it is not. When you come into contact with the allergen, the reaction of your immune system can cause the skin, sinuses, respiratory tract or digestive system to become inflamed.
The severity of allergies varies from person to person and can range from minor irritation to anaphylaxis (a life-threatening emergency situation). While most allergies have no cure, treatments can help relieve allergy symptoms.