Allergies occur when your immune system reacts to a foreign substance—such as pollen, bee venom or pet dander—that doesn’t cause a reaction in most people.
Your immune system produces substances known as antibodies. Some antibodies protect you from unwanted invaders that could make you sick or cause infection.
The severity of allergies varies from person to person and can range from minor irritation to anaphylaxis—a potentially life-threatening emergency.
Allergy symptoms depend on the substance involved and can involve the airways, sinuses and nasal passages, skin, and digestive system. Allergic reactions can range from mild to severe. In some severe cases, allergies can trigger a life-threatening reaction known as anaphylaxis.
A food allergy may cause:
An insect sting allergy may cause:
A drug allergy may cause:
Atopic dermatitis, an allergic skin condition also called eczema, may cause skin to:
Some types of allergies, including allergies to foods and insect stings, have the potential to trigger a severe reaction known as anaphylaxis. A life-threatening medical emergency, this reaction can cause you to go into shock. Signs and symptoms of anaphylaxis include:
Allergy treatments include:
Another form of immunotherapy is a tablet that’s placed under the tongue (sublingual) until it dissolves. Sublingual drugs are used to treat some pollen allergies.