Histamine is a chemical that is found naturally in some foods. In addition it is also a chemical that is released as part of an allergic reaction. When released in this way it causes itching, sneezing, wheezing and swelling type allergy symptoms.
An enzyme called diamine oxidase is responsible for breaking down any histamine that we absorb from a histamine-containing food. If this works well then when we eat a food which contains histamine it does not affect us. Some people have a low level of this enzyme so when they eat too many histamine-rich foods they may suffer ‘allergy-like’ symptoms such as headaches, rashes, itching, diarrhoea and vomiting or abdominal pain. This is called histamine intolerance. Some studies have also suggested links between histamine intolerance and urticaria, asthma, eczema and anxiety and panic attacks.
As well as being responsible for some of the symptoms of allergy Histamine is also a neurtransmitter – a chemical messanger within the brain – so raised levels of histamine in the body can lead to some behavioural problems and mental health issues. For some people high levels of histamine are not due to a lack of the Diamine oxidase enzyme but to a lack of processing of the histamine – thought to be due to undermethylation. There are receptors for histamine in the brain and for some individuals, high levels of blood histamine (called histadelia) have psychological, behavioral, and cognitive symptoms.
What is being measured?
A blood sample is required for the Diamine Oxidase Activity test.
You will need to arrange for a blood sample to be collected by a nurse at your G.P. service or at a private clinic or hospital. Any fee for this service is not included in with the test fee. You may also attend the laboratory in London to have the sample taken.
You will need to send your sample back to the lab via a next day postal service – If you are in the UK, Royal mail offer a suitable next day service. If you are outside of the UK then please check with your postal service for options. The cost of the test does not cover the return postage.
Please note that samples should only be posted on Monday – Thursday so that they do not arrive over the weekend when the lab is closed.
Before Taking the test
If you are wondering if you have Histamine intolerance you may like to eat a diet high in histamine rich foods before completing the test however it is best to get you GP’s opinion about this in case you are having severe reactions. Please do call to discuss this if you are unclear. 01273775480
Diamine Oxidase (DAO) Test
This test looks at the levels of the histamine-degrading enzyme diamine oxidase (DAO).
All sample reports are for representational and educational purposes only. Biomarkers, references ranges, results, and all other data may differ from actual reports. All data included in no way represents an actual patient. Any comparisons of results to actual patients, is completely incidental.