Food allergy - allergic lesions of organs of digestion happen an alimentary, medicinal, bacteriemic and other parentage. The food allergy is observed at the use in nutrition of certain, quite often seasonal products: some vegetables, fruit, berries, mushrooms, rare sea and fish products. The allergy can develop also after reception of medicines (and hits in an organism of other chemical substances), possessing high sensitizing properties (antibiotics, hydrazines, Atophanum, etc.) . Probably allergic lesion of an alimentary system at inhalation entering in an organism of some allergens: pollen of colors, a dust and steams of some chemical substances. Allergens can be also the albuminous antigens formed at disintegration of bacteria, the elementary parasitizing in a gastrointestinal tract, helminths. Allergic reactions can be provoked by a mental condition of the patient, meteorological factors, at women the exacerbation of signs can be bound to a menstrual cycle. Allergic lesions of organs of digestion can be acute and chronic, proceed paroxysmally with more or less long intervals of full absence of signs.

The allergic lesion of a gastrointestinal tract can be shown by small edemas (type of a Quincke's edema), sites of a hyperemia of a mucosa, petechias and larger hemorrhages; the hyperadenosis of an abdominal cavity can be observed. The allergic lesion of a liver meets in the form of cholestatic, less often than a parenchymatous hepatitis and a fatty dystrophia of a liver, in especially serious cases - plural massive necrosises of a hepatic parenchyma. Signs, characteristic for a lesion of organs of digestion, seldom enough come out on top in the general clinical picture of allergic reaction. At a lesion of an esophagus the dysphagia and a retrosternal pain are observed, is usual at a swallowing. The lesion of a gastrointestinal tract is shown by an abdominal pain, sometimes the acute abdominal crisises feigning acute surgical diseases of an abdominal cavity. Gastrointestinal bleedings can be observed. The lesion of a liver is shown by its augmentation, an icterus, change of functional biochemical parameters (aminotransferases, albuminous fractions, albuminous sedimental assays, etc.) . Serious cases - with a massive necrosis of a hepatic parenchyma - proceed was very acutely and come to an end with a hepatic failure and destruction of the patient in some days.