Overview
Allergic conditions are common and increasing cause of illness. In an allergic reaction, first exposure to an otherwise harmless exogenous substance triggers the production of specific IgE antibodies by activated B cells and binds to mast cells. Upon re-exposure, allergen activates mast cells releasing a variety of vasoactive mediators. The severity of allergies varies from person to person and can range from minor irritation to anaphylaxis, a potentially life-threatening emergency. While most allergies can't be cured, treatments can help relieve allergy symptoms.Signs and Symptoms
Sneezing, Itchiness of the nose, eyes or roof of the mouth, Runny and stuffy nose, Conjunctivitis, Swelling of the lips, tongue, face or throat, Urticaria, Itchiness all over the body, Cough, chest tightness, wheezing or shortness of breath, Rash, Facial swelling Worsening of asthma or eczemaCommon Causes
Airborne allergens, such as pollen, animal dander, dust mites and mold, Certain foods, particularly peanuts, tree nuts, wheat, soy, fish, shellfish, eggs and milk, Insect stings, such as from a bee or wasp, Medications, particularly penicillin or penicillin-based antibiotics, Latex or other substances which is in contact with the skin and can cause allergic skin reactionsRisk Factors
Family history of asthma or allergies, such as hay fever, hives or eczema, Children, Have asthma or other allergic conditionInvestigation Techniques
History and physical examination, Full blood count, Skin prick tests, Specific IgE test, Supervised exposure to allergen (challenge test), Serum mast cell tryptase, Peripheral blood eosinophilia (markers for atopic disease)Treatment and Prevention
Avoidance of the allergen , Antihistamines, Corticosteroids, Sodium cromoglycate, Antigen specific immunotherapy, Monoclonal antibody against IgE: omalizumab, Preloaded self injectable adrenaline