Diagnosis and Treatment of Histamine Intolerance

Histamine intolerance is a condition whereby your body is unable to tolerate normal levels of histamine in ingested food and other substances such as wine and beer.

The condition is mainly caused by insufficient levels of an enzyme known as diamine oxidase (DAO), which is responsible for breaking down or digesting the ingested histamine, according to the American Journal of Clinical Nutrition. On a smaller scale, histamine intolerance can be caused by low level of another enzyme called histamine N-methyltransferase, which also degrades histamine.

The main difference between DAO and HNMT is that DAO is found mostly in the gut, while HNMT breaks down histamine in other parts of the body such as the skin and the brain.

Symptoms of Histamine Intolerance

While it is difficult to diagnose, you can discover whether you have histamine intolerance if you regularly experience the following ‘allergy-like’ symptoms after consuming certain foods;

• Skin conditions-This includes itching (pruritus), redness of the skin (flushing), hives, eczema (skin rash) and red spots;
• Gastrointestinal conditions- vomiting, stomach acid reflux, chronic constipation, stomach ache and cramps and diarrhea;
• Vascular complications-fainting, low blood pressure (hypotension), oedema, dizziness and anaphylaxis;
• Respiratory complications- asthma, running nose (rhinitis) and chronic cough;
• In women, symptoms include dysmenorrhoea (chronic period pains), which usually disappear during pregnancy only to reappear once the child is born.

How to Diagnose Histamine Intolerance

While it is hard to diagnose this condition as many foods are rich in histamine and in some individuals, the excess histamine is mainly produced by gut bacteria. To manage this condition, avoid fermented foods, as they have high concentration of histamine.

Moreover, ‘good bacteria’ produce histamine when processing fermented foods. Other foods rich in histamine include:

• Eggs, yogurt, kefir, buttermilk and all forms of fermented milk, such as cheese;
• Citrus fruits such as lime, orange, lemons and grapefruit;
• Dried fruits and various types of berries;
• Seafood such as finfish, shellfish and all kinds of frozen, fresh, canned or smoked seafood;
• Fermented foods such as relishes, sauerkraut, fermented soy, kombucha and pickles;
• Vegetables: spinach and tomatoes (including sauces and ketchup);
• All kinds of cured, processed, fermented and smoked meats such as bacon, pepperoni, sausage, lunch meat and salami, as well as leftover meats;
• Cola, chocolate and cocoa-flavored beverages, tea (normal or herbal) and alcohol;
• Various kinds of spices such as cloves, cinnamon, cayenne, chili powder, curry powder, anise and nutmeg;
• Vinegars and products that contain vinegar such as ketchup, pickles and relishes;
• Artificial food additives and colors;

The best way to detect whether you have histamine intolerance is to eat foods with low concentration of histamine for a few weeks and checking whether your symptoms improve. One thing you should keep in mind is that blood tests, such as the skin prick test, which allege that they can measure the level of the DAO enzyme or histamine levels aren't effective.

Treatment of Histamine Intolerance

A quick way to manage this condition is to take regular antihistamines. You can also avoid the foods rich in histamine, though up to a healthy level to prevent nutritional deficiency. The degree of histamine tolerance varies from one person to another, so it’s prudent to visit a physician to discuss the best way to treat this condition.