A comprehensive review on natural products caused allergy and its mechanism

Various medicinal herbs have pharmacological effects that cause allergic reactions. Due to this reaction many symptoms can be detected, such as rhinitis, nasal decongestant, sneezing, itching, conjunctivitis, and itchy ears or tingling ears. Tickles of asthma, throat cough, wheezing, and other symptoms such as dyspnea, urticaria, dermatitis, bee sting reactions, and so on are less obvious. Individuals develop allergy issues due to overactive immune responses, in which the body produces serum immunoglobulins (Ig) of IgE isotype. In allergic reactions, IgE considers allergens as alien bacteria-so the IgE wants to 'eliminate' them. When IgE binds to the antigenic determinants, chemicals like histamine are released into the body from cells called mast cells, which subsequently leads to a cascade of allergic responses. In this review, we first introduce the immunobiology of allergic response, kinds of allergens and nomenclature of allergens to those who are unfamiliar with the field of allergy. Extensive Information extracted from 203 published literature allergenic substances of natural origin, with emphasis on plant-based materials such as pollens, chemicals from medicinal plants, fruits, latex and their clinical significance in airway allergy, skin allergy is comprehensively discussed. This review provides a comprehensive view of various forms of allergies arising from plant-based materials. Further studies and research are necessary to advance our knowledge of allergies caused by natural products.