Alergens

Alergens are substances that can cause an allergic reaction in susceptible individuals. The immune system normally protects the body from harmful invaders, but in allergic people, it mistakenly identifies certain harmless substances as threats. When exposed to an allergen, the immune system produces antibodies, specifically immunoglobulin E (IgE). These antibodies then trigger the release of chemicals, such as histamine, from mast cells. Histamine and other mediators cause the symptoms associated with allergies.

Common allergens include pollen from trees, grasses, and weeds, which can lead to hay fever. Dust mites, microscopic creatures found in household dust, are another frequent trigger. Animal dander, the tiny flakes of skin shed by pets, can also cause allergic reactions. Certain foods, like peanuts, tree nuts, milk, eggs, soy, wheat, fish, and shellfish, are responsible for many food allergies. Insect stings, particularly from bees and wasps, can provoke severe allergic responses. Mold spores, found both indoors and outdoors, are also common allergens.

Symptoms of an allergic reaction vary depending on the allergen and the individual's sensitivity. They can range from mild, such as sneezing, itchy eyes, and a runny nose, to severe and potentially life-threatening, like anaphylaxis, a systemic reaction that can cause difficulty breathing, a drop in blood pressure, and loss of consciousness. Diagnosis of allergies often involves skin prick tests or blood tests to identify specific IgE antibodies. Management typically includes avoiding known allergens and, in some cases, medication like antihistamines or immunotherapy (allergy shots).