Description: Allergy is an abnormal immune response to a substance that, under normal circumstances, is harmless to most people. This phenomenon occurs when the immune system mistakenly identifies a substance, known as an allergen, as a threat. Allergens can be diverse, including pollen, foods, medications, insect stings, and chemicals. When an allergic person comes into contact with an allergen, their body releases histamines and other chemicals, leading to symptoms that can range from mild, such as sneezing and itching, to severe, such as anaphylaxis, which can be life-threatening. Allergies are common and can affect people of all ages, although some may develop in childhood and disappear over time. The prevalence of allergies has increased in recent decades, leading to greater interest in their study and treatment. Identifying allergens through skin tests or blood analyses is crucial for managing allergies, allowing patients to avoid triggers and receive appropriate treatment.
History: The term ‘allergy’ was coined by Austrian pediatrician Clemens von Pirquet in 1906, who used it to describe an abnormal immune reaction. Since then, the understanding of allergies has significantly evolved, especially with advances in immunology and molecular biology. In the 1960s, skin tests were developed to identify specific allergens, allowing for more accurate diagnosis. By the late 20th and early 21st centuries, the rising incidence of allergies has led to a more intensive focus on research and treatment, including immunotherapy.
Uses: Allergy tests help identify specific allergens that trigger reactions in patients, allowing for more effective management of their symptoms. Additionally, immunotherapy, which involves gradual exposure to allergens, is used to desensitize patients and reduce the severity of allergic reactions. Antihistamines and corticosteroids are also used to relieve symptoms.
Examples: Examples of common allergies include allergic rhinitis, triggered by pollen; food allergies, which can be caused by foods like peanuts or shellfish; and drug allergies, which can occur with antibiotics like penicillin. In severe cases, anaphylaxis can occur after exposure to allergens such as bee stings or certain foods, requiring immediate medical attention.
