Histamine Intolerance

Have you heard of Histamine Intolerance and/or Mast Cell Activation Syndrome/Disorder (MCAS)? These are two very related conditions that can account for a lot of intestinal and systemic symptomatology.

Histamine is a substance released from mast cells, basophils, platelets and certain neurons (mostly in the hypothalamus in our brains), and enterochromaffin cells in skin and intestine. It is released when a cell is triggered by something it reacts to. For example, being allergic to orange tree blossoming causes you to sneeze and have a runny nose--that is your cells releasing histamine when the pollen activated it.

When someone has histamine intolerance the person specifically cannot handle histamine--either over-produces it, or cannot break it down, or both. Around 1% of the population is supposed to have this, but Dr. Morstein sees more because she is looking for it, and nows it can be misdiagnosed for years.

With MCAS, there is an over-reaction by an immune cell in our body, and there are numerous substances secreted, including histamine, that can cause signs and symptoms. They also produce tryptase and chymases, which we can use to measure elevated histamine response through labs. Tryptase is involved with the airway, vascular relaxing, gut smooth muscle movement. Chymases help with blood pressure control, and vascular maintenance. It can cause problems in the kidney cells.

MCAS can be primary, secondary or idiopathic:

1. Primary: Genetic defect in KIT gene

2. Secondary: Activated due to drugs, exercise, infections, venom, hypoxia, extreme temperatures, neuropeptides, lipoproteins, inflammatory substances, environmental toxins, mental/emotional trauma, intestinal parasites/fungal overgrowth/SIBO/bacterial dysbiosis. MOLD toxicity is a common cause.

3. Idiopathic: Unknown reason

So, you can have histamine intolerance by itself or histamine intolerance can be an indicator of MCAS, but it doesn't mean you have MCAS, unless other mediators are also elevated.

What causes HI/MCAS? Many things can cause it! Many common medications (BP meds, anti-inflammatory, opioids, diuretics, antibiotics, muscle relaxants, anti-depressants and others); DAO/HNMT enzyme genetic deficiency; environmental toxins particularly MOLD, as well as chemicals and toxic metals; gut upset from parasites, fungal overgrowth, SIBO/SIFO, bacterial dysbiosis. Particularly when it is caused by mold/mycotoxins, it can get very bad and cause Chronic Inflammatory Reaction Syndrome (CIRS), a progressive, multi-system illness from being exposed to biological toxins.

Histamine Intolerance and MCAS can affect nearly every part of the body: fatigue, malaise; nasal congestion/sneezing/itching, asthma, throat swelling; anxiety, depression, poor attention/concentration, insomnia, migraines: muscle/bone ache, osteopenia and osteoporosis; digestive cramps, diarrhea, esophageal reflux, nausea/vomiting; skin flushing, itching, hives, swelling; low blood pressure, fainting, light-headed, racing heart rate.

Generally symptoms develop if you have too much histamine coming in, too little being broken down, or deficiencies in DAO/N-MT enzymes.

Lab testing for Histamine includes:

1. Tryptase

2. Histamine: Plasma and urinary

3. DAO

4. N-methyl histamine 24 urine

5. Nutrients: Serum copper, B6 plasma, Vit C plasma, Vit D3--all needed to reduce Mast Cell breakdown and histamine release.

Treatments:

1. Testing to uncover reason for histamine/mast cell problem. Working on gut overgrowth of fungal, SIBO, bacteria is important and checking for mold exposure and toxicity is also helpful.

2. Low Histamine Diet -- many foods contain histamine as presented, or as leftovers. A low histamine diet is necessary to start with to prevent ingestion of high levels. Many things such as alcohol, processed meat, leftovers, cheeses, fermented foods, some vegetables and fruits (especially tropical), fish, nuts and peanuts, chocolate, additives. Dr. Morstein gives patients a helpful dietary list of foods to eat and avoid.

3. Diamine oxidase-enzyme responsibility for metabolizing ingested histamine in foods; it deactivates 80% of ingested histamine. We have DAO as a supplement that helps some people but not others, as not everyone with a histamine problem under-produces DAO. Another enzyme M-methyltransferase scavengers and inactivates the other 20% of histamine but we do not have that as a supplement.

 Medications--Prescription or Compounding: These are frequently suggested and can be very safe and valuable. Dr. Morstein would decide which are the best for each patient.

1. Histamine blockers: H1 blockers and H2 blockers

2. Leukotriene inhibitors: Singulair

3. Mast Cell Stabilizers: Cromolyn sodium, Ketotifen, hydroxyurea

4. Immune system balancer: Low Dose Naltrexone

Supplements: These are always given and can be very valuable. Dr. Morstein would decide which are the best for each patient.

1. Histamine homeopathic drops

2. DAO enzyme

3. Bioflavinoids

4. Vitamin C

5. Many botanicals can be very helpful and Dr. Morstein helps decide which are best for each patient.

Histamine Intolerance and MCAS are becoming more common. Dr. Morstein works with patients regularly with this and has even lectured on histamine in SIBO patients. If you feel this is a problem, please contact Dr. Morstein for advice, investigation and a comprehensive protocol.