[Interactions between ethanol and histamine].

Histamine is biogenic amine that exerts the numerous important biological functions. Alcohol affect histamine action because those have common metabolizing enzymes--aldehyde dehydrogenase and aldehyde oxidase. Acetaldehyde can compete with aldehydes derived from histamine metabolism. Increased blood acetaldehyde resulting from abnormalities of alcohol dehydrogenase genotype in the Orientals population can release histamine from mast cells and basophiles, which induces the hypersensitivity reactions (flushing). These reactions may be blocked by antihistamine drugs. H2-receptor antagonists influence on the ethanol metabolism by the inhibition of the activity of alcohol metabolizing enzymes in the stomach and liver. Decreased activity of stomach alcohol dehydrogenase results in an increase in the blood ethanol concentrations, which may impairs the psychomotor skills and exceeds legal limits of driving. There are same evidences that ethanol affects the brain histamine level by the changes in the activity of enzymes involved in the synthesis and metabolism of histamine.