The clinical evidence for histamine intolerance is based on chronic headache, diarrhoea, vomiting, flush, urticaria, asthma-like symptoms, rhinitis and others.
Prevalence and risk factors of urticaria with a focus on chronic urticaria in children. Allergy Asthma Immunol Res 2017;9:212–219.
[…] sausages, fish) cause above-normal serum histamine levels. 3 These elevated histamine levels cause various histamine receptor–mediated symptoms such as flush, headache or urticaria