Histamine intolerance can be caused by a deficiency or an inhibition of Diamine Oxidase (DAO), which is the enzyme responsible for the breaking down histamine in our gut. Histamine can lead to allergic-type reactions after consumption of certain foodstuffs. A simple blood test will reveal whether your symptoms are being driven or worsened by an underlying histamine intolerance.
Symptoms of DAO deficiency or histamine intolerance:
Itching, red skin