Allergies are among the most common chronic conditions worldwide. Allergy symptoms range from making you miserable to putting you at risk for life-threatening reactions. According to the leading experts in allergy, an allergic reaction begins in the immune system. Our immune system protects us from invading organisms that can cause illness. If we have an allergy, immune system mistakes an otherwise harmless substance as an invader. This substance is called an allergen.
An allergic reaction typically triggers symptoms in the nose, lungs, throat, sinuses, ears, lining of the stomach or on the skin. For some people, allergies can also trigger symptoms of asthma. In the most serious cases, a life-threatening reaction called anaphylaxis can occur. The most common allergens that are responsible for allergic reactions are pollen, dust, food, insect stings, animal dander, mold, medications, latex. If 5% of the child population have food allergy, the risk that a food allergic child will die from a food allergic reaction is about 1 in 800 000 per year.
Although avoiding the allergen is an important treatment approach, it usually does not completely resolve the allergic reaction. Medications such as antihistamines, decongestants or a combination of over-the-counter and prescription medications are used to treat allergy symptoms. Nasal sprays such as topical nasal steroids and cromolyn sodium also can be used to treat allergy symptoms. Asthma medications, which reduce allergy symptoms include inhaled steroids, inhaled and oral bronchodilators, oral anti-leukotrienes and zyflo, and injected medications including an antibody such as omalizumab.