Allergies An allergy is an abnormal reaction or hypersensitivity to an environmental or food substance that is usually harmless. These substances, called allergens, provoke the immune system into making antibodies and releasing histamine, which cause a wide variety of allergic symptoms. Allergic reactions occur most often in the respiratory system, eyes and skin, but can involve any body system. The most common environmental substances that elicit an allergic reaction include dander, dust, dust mites, mold, pollen and tobacco smoke. Typical food allergens include chocolate, corn, dairy products, eggs, food dyes and additives, peanuts, tomatoes, shellfish, and wheat.
Allergies can cause mild symptoms like sneezing, runny nose and itchy eyes.
They can also precipitate more serious and chronic respiratory conditions like asthma and bronchitis . Allergies may be a contributing factor in disorders such as migraines, rheumatoid arthritis, diabetes and gastrointestinal disorders. The most severe allergic reaction, anaphylaxis, affects many body systems. Acute allergic episodes that involve multiple body systems or compromise breathing are a medical emergency and you should seek emergency medical attention at once. The primary treatment of serious allergies should be with conventional medicine.