Histamine Intolerance: Symptoms, Diet & Treatment

Histamine intolerance may be a new term for many people. However, the symptoms associated with it are common.

• Rashes, Hives or Eczema
• Headaches or migraines
• Diarrhea
• Low blood pressure
• Itchy eyes/runny nose/congestion
• Premenstrual cramping or headaches

These are general conditions and have many potential causes, but one possible cause is histamine intolerance.

Histamine is a chemical found in all cells of the body.  It is a natural component of many foods and an important part of the immune and nervous systems.  It also plays an important role in inflammation.

Histamine intolerance (HIT) is thought to be related to a build-up of histamine. In a healthy person, histamine is broken down by two enzymes: DAO and HNMT. Symptoms may occur when one of these enzymes isn’t working correctly. DAO is made in the intestines. If the intestines are not healthy, there may not be enough DAO to break down histamine normally. When build-up occurs, so do symptoms.

Decreased DAO levels may explain why histamine intolerance symptoms are more common in persons with gastrointestinal disorders such as inflammatory bowel disease, IBS, celiac, and SIBO. DAO activity can also be blocked by certain medications.

The following are the most common symptoms of histamine intolerance

• Diarrhea
• Headache
• Flushing
• “Histamine Rash” /Urticaria (hives)/eczema
• Arrhythmia ( irregular heartbeat)
• Low blood pressure due to vasodilation caused by the histamine
• Wheezing
• Runny nose
• Watery eyes
• Angioedema-swelling of face/hands/lips
• Heartburn-due to increased acid production
• Itching- typically of the skin
• PMS- Headaches around the menstrual cycle or painful cramps due to histamine-induced contractions in relation to hormone levels

Histamine intolerance is more common in people with underlying intestinal problems such as inflammatory bowel disease, celiac disease, IBS, SIBO etc.  There is minimal information on the actual incidence of histamine intolerance. Its correlation with other health issues is emerging.

Histamine intolerance symptoms can be triggered by certain foods.  But it is different than a food allergy. Some of the symptoms mimic a true allergic reaction, but the reaction is different than an allergy, so skin testing and blood allergy tests will be negative.

HIT is thought to be due to a build-up of histamine. Because of this, the symptoms may not be immediate. Symptoms may be triggered any time your “threshold” is reached. Because of this, it may be difficult to pinpoint a particular culprit.

For example, you may have consumed high histamine foods in the morning but low histamine food in the afternoon. Even though the food in the afternoon food was low in histamine, it put you over your level of tolerance. So, symptoms occur in the afternoon. You might think your symptoms were due to the afternoon food but in reality, the morning foods were more problematic.

If you think you might have histamine intolerance, speak to your physician to evaluate other possible “look-alike” conditions.  Conditions such as true allergies, mast cell disorders, or underlying digestive disorders can look similar to histamine intolerance. If these possibilities have been evaluated and addressed, an elimination diet may be initiated to see if symptoms improve. A food diary is essential. Underlying issues must be corrected first for the best outcome. Because the diet is restrictive, please consult a professional to ensure proper nutritional intake.

At this time there are no proven tests to diagnose histamine intolerance.  A trial of a low histamine diet is used to determine the presence of histamine intolerance.  It is possible to measure blood DAO activity (one of the enzymes listed above), and histamine levels. These results do not seem to correlate with symptoms. Typical blood allergy tests or skin testing will not be positive, as HIT is not IgE mediated (like true allergies).

It is important to remember that while considering HIT as a cause of symptoms you must evaluate for related disorders such as true allergies, mast cell disorders, inflammatory bowel disease, celiac disease, fructose malabsorption, small intestinal bacterial overgrowth, colitis, etc.

After the evaluation of related disorders, a diet eliminating high histamine foods may be pursued. If symptoms improve when histamine is lowered or eliminated from the diet you may be histamine intolerant.

Treat any underlying disorder first. This may improve the histamine tolerance.

I generally like to focus on dietary treatments because I prefer to do as much as possible with diet instead of medication. But, histamine intolerance truly requires an integrative approach, as it often occurs in conjunction with other disorders that need to be addressed beyond dietary modifications.

Diet: A low histamine diet is the treatment of choice (food lists are below). This can be challenging if someone is already on a restricted diet such as a gluten-free or low FODMAP diet and should be done under the care of a health care practitioner so that proper nutritional intake is maintained. The tolerance to histamine varies from person to person and the amount of histamine tolerated must be deduced by trial and error. Some people can only tolerate very small amounts and others can be more liberal.

What is important to note is that tolerance to histamine seems to improve once underlying issues are addressed. For example; if IBS or SIBO are treated, reactions to histamine often decrease. It is imperative to treat the underlying disorder in conjunction with dietary changes.

Once the elimination diet is completed one must individually assess tolerance to particular foods and liberalize the diet as tolerated so that optimum nutrition and lifestyle are attained.

Sleep: 7-8 hours a night helps everything!

Support: Health issues and dietary restrictions are stressful and challenging. Seek out support from family, community, faith organizations, online support groups, local support groups. Avoid those who provide negative interactions. Negative interactions delay healing.

Exercise: Any exercise is helpful. Aim for 30-60 minutes daily. Don’t feel bad if you only fit in 15 – it still helps!

Relaxation: The benefits of relaxation techniques cannot be emphasized enough. Breathing exercises or progressive muscle relaxation are easy, portable, and free. Yoga and meditation are great as well. Relaxation for you may also be reading, enjoying time with friends, or playing music.

Medications: Antihistamines, topical steroids/creams, oral steroids, topical homeopathic or plant-based creams, and lotions for rashes.

Supplements: There is little to no data on these, but the following are sometimes used. Vit C, B6, Zn, Cu, Magnesium, Mangosteen, Quercetin, DAO promoters and supplements, topical creams. Please use any supplement under the guidance of a practitioner. Supplements can have toxic side effects.

Histamine content app: https://itunes.apple.com/us/app/food-intolerances/id419098758

Symptom tracker app: https://itunes.apple.com/gb/app/mysymptoms-food-diary/id405231632?mt=8&ign-mpt=uo%3D4

Books: Try a low histamine cookbook. It will make preparing meals easier, especially during the elimination phase.

• Eat fresh food as much as possible
• Fresh meat and fish (avoid canned meat and fish)
• Fresh fruit, except strawberry, citrus
• Fresh vegetables, except tomatoes, spinach, and cabbage
• Grains: rice, corn, millet, oats, sorghum
• Oils: Most cooking oils

See below for lists of high histamine foods

• The histamine content of food varies depending on the duration of storage, ripeness or maturity, cooking, and processing.
• Certain foods may also not be high in histamine yet are high in compounds known as histamine liberators which can trigger similar symptoms by increasing histamine levels.

The list below contains commonly accepted high histamine foods/histamine liberators. This list is by no means exhaustive. Available lists vary and consistent data is hard to find on the histamine content of foods.

Fermented and aged foods are some of the biggest culprits.

• Alcohol: Champagne, red wine, beer, white wine,
• Fermented or smoked Meats/Fish: Sardine, mackerel, herring, tuna, salami
• Pickled or canned foods: Sauerkraut, pickles, relishes, soy sauce
• Fermented milk products: Yogurt, kefir, buttermilk
• Aged cheeses: Parmesan, Gouda, Swiss, cheddar.
• Fruit: Dried fruit, strawberries, citrus
• Vegetables: Tomatoes and tomato products, spinach
• Legumes: Chickpeas, soybeans, peanuts
• Other: Cinnamon, chocolate
• Grains: Wheat
• Histamine releasers: Citrus, papaya, pineapple, nuts, strawberries, egg white, additives
• DAO blockers: alcohol, black and green tea

These medications block the DAO enzyme:

• Acetylcysteine
• Aspirin
• Ambroxol
• Aminophylline
• Amiloride
• Amitryptiline
• Cefuroxime
• Cefotiam
• Cimetidine (Tagamet)
• Ciprofloxacin
• Cyclophosphamide
• Contrast Media
• Docein
• Diazepam (Valium)
• Haldol
• Metamizol
• Metoclopramide (Reglan)
• Naproxen (Aleve)
• Narcotics-Thiopental (IV med. for surgery)
• Noscapene
• Pancuronium
• Prilocaine
• Verapamil

• Histamine Intolerance: The Current State Of Art : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463562/
• Comparing Histamine Intolerance And Mast Cell Disorder: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463562/
• Considering Histamine In Functional GI Disorders: https://pubmed.ncbi.nlm.nih.gov/32643952/
• Non-responsive Celiac Disease And Histamine Intolerance: https://pubmed.ncbi.nlm.nih.gov/33268003/
• Histamine Intolerance And Functional Gut Disorders-https://pubmed.ncbi.nlm.nih.gov/32643952/

THIS ARTICLE IS COPYRIGHTED BY AMY BURKHART, MD, RD.