allergènes

Allergènes are substances that can cause an allergic reaction in susceptible individuals. The immune system normally protects the body from harmful invaders, but in people with allergies, it mistakenly identifies a harmless substance, known as an allergen, as a threat. This triggers an immune response, leading to the release of chemicals like histamine, which cause allergy symptoms.

Common allergens include certain foods, such as peanuts, tree nuts, milk, eggs, soy, wheat, fish, and shellfish. Environmental allergens are also prevalent and include pollen from trees, grasses, and weeds, as well as dust mites, mold spores, and animal dander. Insect venom, from stings or bites, and certain medications can also act as allergens.

The symptoms of an allergic reaction can vary widely in severity and presentation. They can affect different parts of the body, including the skin (hives, eczema), respiratory system (sneezing, coughing, wheezing, nasal congestion), and digestive system (nausea, vomiting, diarrhea). In severe cases, a life-threatening allergic reaction called anaphylaxis can occur, characterized by a rapid drop in blood pressure, difficulty breathing, and loss of consciousness.

Diagnosis of allergies typically involves a medical history, physical examination, and specific tests, such as skin prick tests or blood tests, to identify the offending allergen. Management of allergies focuses on avoiding known allergens, as well as using medications like antihistamines or corticosteroids to alleviate symptoms. For severe allergies, emergency epinephrine (adrenaline) is prescribed.