What does the term "allergy" refer to?

The term "allergy" specifically refers to an abnormal immune response to a foreign substance, known as an allergen. This can manifest in various forms, such as respiratory issues, skin reactions, or digestive problems, depending on the individual and the substance involved. Allergies occur when the immune system mistakenly identifies a harmless substance as a threat and mounts an inappropriate response. This can lead to symptoms that range from mild to severe, including anaphylaxis, which is a life-threatening reaction. The understanding of allergies as immune responses forms the basis of many treatment and management strategies, such as avoidance of known allergens and the use of antihistamines or other medications to alleviate symptoms.