Allergy Reaction: Allergy occurs due to hyper immune reaction to an Antigenic stimulus. Initial exposure to an antigen causes a stimulation to produce antibodies and subsequent antigenic stimulus of the same antigen leads to aggrevated production of immune reaction leading to an inflammatory hypersensitivity reaction.
Peanut protein acts as an allergen in very susceptible individuals leading to an inflammatory reaction to Peanut protein. Peanut protein has a molecular weight of 63,500 daltons and leads to an immune reactions in susceptible individuals