An allergy is a reaction by immune system to some foreign substance in body.Immune system produces substances known as antibodies. When someone have allergies, the immune system makes antibodies that identify a particular allergen as harmful, even though it is not.
When person come in to contact with allergen, its immune system’s reaction can inflame your skin, sinuses, digestive system or respiratory system. Severity of allergies varies from person to person and can range from minor irritation to anaphylaxis — a life-threatening emergency.
As per one research article about 20-30% of Indian population suffers from at least one allergic diseases, from which 55% cases are of allergic rhinitis.
Common allergens may include:
Allergies are of different types and the symptoms may vary for each of the type:
Symptom of Anaphylaxis
Diagnosis of allergy is based in symptoms, physical examinations, various exposure and food habit
Your doctor might also recommend one or both of the following tests