What happens to the immune system when a person has allergy?

When a person has an allergy, their immune system overreacts to a substance that is typically harmless, such as pollen, dust mites, or pet dander. This overreaction can cause a variety of symptoms, including sneezing, a runny nose, itchy eyes, and difficulty breathing.

When a person with an allergy comes into contact with an allergen, their immune system produces antibodies called immunoglobulin E (IgE). These antibodies attach to cells in the body called mast cells. When the allergen comes into contact with the mast cells, it causes them to release histamine and other chemicals. These chemicals cause the symptoms of an allergic reaction.

In some cases, an allergic reaction can be severe and even life-threatening. This is known as anaphylaxis. Symptoms of anaphylaxis include difficulty breathing, swelling of the throat, and a rapid drop in blood pressure. If you experience any of these symptoms, it is important to seek medical attention immediately.

Allergies can be managed by avoiding allergens, taking medication, and immunotherapy. Avoidance is the most effective way to manage allergies, but it is not always possible to completely avoid all allergens. Medication, such as antihistamines and decongestants, can help relieve the symptoms of allergies. Immunotherapy, also known as allergy shots, can help reduce the severity of allergic reactions over time.