Allergies occur when your immune system reacts to a foreign substance like pollen, dander, food etc. When you have allergies, your immune system makes antibodies that identify a particular allergen as harmful. This leads to problems in your skin, sinuses, airways & digestive system. Severity of allergy varies from person to person. Common allergy triggers are: Airborne allergens like pollen, animal dander, house dust, mites; Foods like peanuts, tree nuts, wheat, soy, eggs, fish, milk; Insect bite like bee or wasp; Medicines like penicillin; Latex or other substances you touch. You are more likely to develop allergies if there is a family history or if you suffer from Asthma. Atopic allergy implies a familial tendency to manifest conditions like Asthma, Rhinitis, Urticaria and Eczematous dermatitis either alone or in association with the presence of IgE. Some individuals without atopy may develop hypersensitivity reactions due to presence of specific IgE.