allergenic

adj. causing allergic reactions

Most humans mount significant IgE responses only as a defense against parasitic infections. However, some individuals mount an IgE response against common environmental antigens. This hereditory predisposition is called atopy. In atopic individuals, non-parasitic antigens stimulate inappropriate IgE production, leading to type I hypersensitivity. A nonparasitic antigen capable of stimulating a type I hypersensitivity reaction in atopic individuals is called an allergen.
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Adjective
1. relating to or having the effect of an allergen
(pertainym) allergen

adjective
which produces an allergy; the allergenic properties of fungal spores
allergenic agent = substance which produces an allergy

ALLERGENICO