Allergy:

Allergy is a disorder of the immune system often also referred to as autopsy. Allergic reactions occur to normally harmless environmental substances known as allergens; these reactions are acquired, predictable and rapid. Strictly, allergy is one of four forms of hypersensitivity and is called type I (or immediate) hypersensitivity. It is characterized by excessive activation of certain white blood cells called mast cells and basophiles by a type of antibody known as IgE, resulting in an extreme inflammatory response. Common allergic reactions include eczema, hives, hay fever, asthma, food allergies, and reactions to the venom of stinging insects such as wasps and bees. 

An other main cause is inflammation inside nose may be in the polypus, may be in the bone, which is creating sensitivity, that is allergy. Lot of sneezing with runny nose are main symptoms of this disease.

Polycum RA-17 is the best remedy to cure the sensitivity

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Polycum RA-17/Q is a useful product for application to remove the inflammation inside nose.