This test requires a blood draw, so please ensure you can refer to a phlebotomist in the clients area before you order this test.

Histamine is broken down in the body via the enzyme DAO (diamine oxidase) and histamine N-methyltransferase. The newly developed THAK test determines the total histamine degradation capacity, regardless of which degradation pathway is relevant. By this, it has clear diagnostic advantages against measurement of DAO activity or DAO concentration. Current research shows that THAK is independent of dietary histamine content and delivers reliable results under a histamine elimination diet

Tests for:

Histamine intolerance via total histamine degrading capacity.

Symptoms and conditions:

• Migraine
• Headache
• Dizziness
• Gastrointestinal complaints
• Soft stools
• Tachycardia, arrhythmia
• Hypotension
• Menstrual pain
• Rhinitis
• Dry nose
• Asthma
• Depressions
• Skin irritation

Causes of intolerance: 

1) Consumption of foods rich in histamine, such as:

• Fish: e.g. tuna fish, sardine
• Cheese: e.g. Emmental, Gouda
• Vegetables: e.g. sauerkraut, spinach
• Smoked meat: e.g. salami
• Alcohol: e.g. red wine, sparkling wine
• Vinegar: e.g. balsamic vinegar

After the consumption, the histamine concentration in the blood will increase. In particular foodstuffs that ripen for a very long time or that are stored for a very long time, have a high content of histamine that may cause problems depending on DAO activity.

2) Consumption of biogenous amines & histamine liberators, such as:

• Chocolate and cocoa
• Citrus fruits
• Nuts
• Pulses
• Wheat germs
• Black and green tea
• Tomatoes
• Strawberries, bananas, pineapples,
• Kiwifruits, papaya, raspberries, pears

In case of a high consumption of biogenous amines, DAO is no longer available in sufficient quantities for the degradation of histamine. Other foodstuffs, so-called histamine liberators, can release the body’s histamine and thus have a negative influence on the histamine level in the body.

3) Inhibition of the enzyme by intake of:

• Alcohol
• Drugs like e.g.: acetylcysteine, ambroxole, aminophylline, amitriptyline, chloroquine, clavulinic acid, isoniazid, metamizole, metoclopramide, propafenone, verapamil

The inhibition of the DAO enzyme results in histamine intolerance. Possible potent inhibitors of DAO are in particular alcohol, but also some common drugs.

4) Affected intestinal flora:

An affected intestinal flora produces considerable quantities of histamine and other biogenous amines that lead to an additional inhibition of DAO.

5) Vitamin B6 and copper deficiency:

Copper is a central component of DAO. A deficiency of copper results in not enough DAO being produced. Vitamin B6 is a co-factor of DAO. Without vitamin B6, the enzyme is not able to degrade histamine.

6) Congenital deficiency of DAO:

This very rare type of histamine intolerance is based on a congenital enzyme defect due to which the enzyme is not produced in sufficient quantities.

Method:

Radio Immuno Assay (RIA)

Blood Draw Procedure (for professional use only)

Information for the doctor or phlebotomist on how to take the sample:

Yellow topped SST and red topped amber transfer tube

• Draw the Yellow topped SST fully.

• Place upright in a rack at room temperature for 20 to 30 minutes to allow blood to clot.

• Centrifuge the Yellow topped SST for 15 minutes. The serum must be free of hemolytic or red blood cells.

• Pipette all the serum from the Yellow SST into the red topped amber transfer tube. 

• Cap transfer tube tightly.

• Check patient details are written on red topped amber transfer tube.

• Place the tube into the plastic tube holder along with the absorbent pad and place into the bio-hazard bag.

• Christian Lutz, C., Frost, G., Knittel, T.& Missbichler, A. (2018) Characterization and Potential Clinical Application of a Novel Test System for the Quantification of Histamine Degradation Activity in Humans
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463562/