Allergies and Your Genes – Histamine, Autoimmunity and DAO SNPs

The other day I was reading an article that discussed histamine as it pertains to allergies to pollen, like sneezing and itchy eyes. It made me realize that almost everyone assumes histamine causes allergies and nothing else. This is simply not true. 

Histamine can certainly cause allergies, and it is found in hundreds of foods that you consume daily, but an allergy is different than what I want to share with you today. An allergy causes an almost immediate reaction to the food you just ate, whereas an “intolerance” is a reaction that occurs later. Why later?  Because the blood levels of histamine need to spike for the reaction to take place, you are reacting to histamine, not the food itself.  See the difference? 

High blood histamine levels will cause chronic health conditions, which could be life-long. In contrast a true food “allergy” results in symptoms within a few minutes like lip swelling, itchiness, sneezing, hives, diarrhea and possibly anaphylaxis.

Histamine is associated with many problems so read on, this could be life-changing information for some of you.  In fact, I’ll just tell you right now that eating leftover meats can produce too much histamine and you’d never sneeze from that. The histamine is produced because bacteria act on your leftovers and produce histamine, then you eat it.

A problem with histamine break-down can cause many disorders that you would never connect to histamine (since you associate histamine with sneezing and runny nose). For example, people who are directed to eat fermented foods, common with Hashimoto’s, can experience a worsening of their thyroid condition due to high histamine found in fermented foods and the inability to break it down! I’ll circle back to this later.

Anxiety and irregular menstrual cycles is very common in women with high histamine. It causes blood vessels around your brain to swell, increasing pressure in your head causing migraines and cluster headaches.

If your face turns red when you drink wine, histamine is to blame.

It’s not that you have an “allergy” like you would to pollen, it’s more that you have an intolerance. So use the right word when discussing this with your physician.

Histamine is a naturally-occurring compound that your immune system produces when faced with antigens like pet dander, pollen and other allergens. This is where antihistamines like Claritin and Zyrtec work.  They reduce excessive amounts of histamine which is released like crazy from cells called “mast” cells.  So a person with hyperactive mast cells will dump a lot more histamine than they should. 

I want you to know that histamine is not bad, in fact, it acts as a neurotransmitter. A certain type of histamine helps you make stomach acid, which helps you break down food during digestion. It is this area where Zantac and Pepcid work, they reduce histamine 2.   

Histamine levels can get out of control and it’s ironic that you associate high histamine with your head (all the sneezing, itchy, red eyes, scratchy through, mucus and so forth) the truth is the high histamine can stem from intestinal problems.  It can also stem from your genetic profile (your SNPs) which I’ll cover shortly.

First the gut problems.

Gut problem termed SIBO (small intestinal bacterial overgrowth) can lead to elevations in histamine as well as serum cobalamin. The colonization of germs in your small intestine will increase histamine levels and therefore symptoms. So will an ulcer (it’s due to GI bleeding). High histamine may also be the result of a very permeable intestinal wall (leaky gut as we affectionately call it).  Eating histamine-rich foods can also jack up levels rather quickly.

That expensive bottle of 1998 vintage Petrus Pomerol is not worth the $1500 a bottle if you have an activated DAO SNP! Main point, having the SNP in your gene pathway doesn’t mean you have histamine intolerance, but you are pre-disposed. You may be active, but it’s not a 100% certainty okay. Let me assume for the purpose of my blog today that you have the SNP and it IS active so you have a chronic health condition of some sort.  

Skip the red wine, especially the expensive ones, they are still often full of sulfites. That smoked turkey sub and yogurt you had for lunch is also high in histamine. So is anything fermented like kefir, bleu cheese or sauerkraut. I included a comprehensive list of histamine-rich foods, as well as histamine-provoking foods in my Headache Free book in case you have that. 

Let’s talk about your genes now.  SNPs for DAO can easily be tested for, usually a salivary test. A homozygous SNP in DAO can produce histamine intolerance.

Histamine intolerance can be the result of a Diamine Oxidase (DAO) deficiency. FYI, I have 2 heterozygous SNPs in the DAO gene myself. Having several active SNPs in your DAO gene pathway could cause a DAO deficiency. DAO breaks down histamine in the gut. It’s like a big ax that chops it up, so if you don’t have the ax you can’t chop it up. Histamine backs up in your bloodstream and causes discomfort and illness. People with DAO problems have an intolerance, not a true “allergy.”   The problem is so grand that I’m betting it costs our healthcare system millions of dollars. 

Another SNP in the HNMT gene (histamine-N-methyl transferase) will cause histamine to build up. This is the gene that encodes for an enzyme that reduces histamine into another compound called N-methylhistamine, which subsequently requires the MAO (monoamine oxidase) enzyme to further break it down.  MAO runs by having enough riboflavin (actually the biologically active form called FAD).

Anyway, a polymorphism that blocks HNMT prevents the break down of histamine, just like a SNP in the DAO enzyme will cause histamine to accumulate.  Either SNP, your histamine builds up too high. 

What if you don’t have a SNP, is it still possible to have these enzymes malfunction, and thus have histamine build up? 

You betcha! That’s what you have me for. I’m a pharmacist, so I know medications like the back of my hand. And I can assure you that certain medications will act as “drug muggers” on a pathway, stealing the very nutrients you need to make that pathway run. If you run out of a nutrient that runs a specific pathway, then the pathway stops working. It’s kind of like a double homozygous SNP that is expressing, but it occurs from medicines you take (that rob the necessary nutrients).  I call it a “Medication-Induced SNP” or MIS because that’s exactly what it is.  Take a look at this pathway I drew.
Screen Shot 2015-10-17 at 2.45.58 PM
As you can see from my diagram, the DAO enzyme is dependent on vitamin B6, B12, iron, copper and vitamin C.  Diuretics, hormone replacement drugs, vibrates and statins (and others) deplete these nutrients thus causing a MIS… the acronym for “medication induced SNP”  and the first letters form “MIS” as you can see. 
Yes I made that up, but you will see me using that term from now on. 

So a Medication-Induced SNP can happen in the absence of an actual gene SNP. The medication is acting like the homozygous polymorphism, only worse. You see, having a polymorphism doesn’t mean you will have expression of the SNP, whereas (and this is highly unfortunate) taking a medication is a slam dunk for expressing what looks like a SNP! It is definitely going to be a ‘drug mugger’ of nutrients, thus it is definitely going to hinder your pathways and either upregulate or downregulate a biochemical pathway. How much did I make to discover this?  
Zero, but my research will hopefully make your life better and spark discussions all over the world. If you have more interest in how medications are inducing SNPs, I’ve created the world’s first resource and this is especially handy for practitioners, and savvy consumers. It’s laminated pathways on a keyring, with all the medications embedded on the pathways. You can click here to learn about my keyring pathyways.

In the case of the HNMT and MAO enzyme, the following drugs deplete riboflavin which is needed to run that enzyme: Hormone replacement, diuretics and certain antidepressants.  Those categories of drugs cause a MIS “medication induced snp” and effectively cause histamine to build up in your bloodstream. 

This part is huge: 
If your physician doesn’t tease these problems (either a  DAO block or an HNMT block) caused by medications you take, or by polymorphisms you have, then the following may happen to you:

* You might get a diagnosis for “migraines” or “cluster headaches” and you are given a lazy-Susan of drugs to reduce headache frequency. For example:
1) Triptans like Imitrex or Zomig
2) Pain-killers like Vicodin or Dilaudid
3) Anti-inflammatories like Naproxen

Do you know that cluster headaches (extremely painful and disabling) are also called “the histamine headache” because they are so commonly associated with high levels of histamine.

* You might get a diagnosis of anxiety and be prescribed a benzodiazepine drug (alprazolam for example). Anxiety is very prevalent among vegans, and I suspect it’s due to their high consumption of tofu and tempeh two fermented foods that are extremely high in histamine. Vegans who are prone to anxiety or other mood instability problems should consider a trial diet where they eliminate the fermented foods altogether (every one of them including kombucha, sauerkraut and tofu/tempeh). See how you feel after a month or two.  You don’t have to eat animals if you don’t want, but at least animal protein is not fermented, it’s better for you than the manufactured fermented stuff.

* You might experience a worsening of Hashimoto’s thyroiditis  if you have histamine intolerance. It’s sad but true that many Hashi patients are told to eat certain foods to help repair their gut, but the recommended foods are fermented. That’s dangerous to a Hashi patient. The problem is that fermented foods are extremely high in histamine. Hashimoto’s patients all have inflamed “leaky” guts with too many bad bacteria and yeast, and too few healthy bacteria. This imbalance predisposes you to more food sensitivities so when you eat fermented foods (or any other food high in histamine for that matter), you make yourself sicker.

More specifically, experts that recommend diets high in fermented foods (with good intentions to support gut health), cause a low-grade inflammatory cytokine problem in their Hashi patients. The reason it backfires is due to increasing the histamine levels (from the foods eaten), combined with a problem breaking down the histamine consumed. This could be from a SNP in your DAO gene or histidine decarboxylase gene. It could be a Medication-Induced SNP too, if the patient takes a drug that mugs any of the nutrients needed to run DAO. Remember, DAO breaks down histamine in the intestines (it doesn’t help you with allergens like dust).

So anyway, histamine builds up and may cause a worsening in a Hashi patient. This can also occur from antibiotic use, or other drugs that have chipped away at your microbiome like oral contraceptives and acid blockers. So I would never recommend the histamine-rich foods (listed below) if you have hypothyroidism or Hashimoto’s until you are certain that your blood histamine levels are well within normal levels, and also certain that you do NOT have a DAO snp.

* Stomachaches or Diarrhea. You may be told that you need to go off gluten, and not that this is a bad idea, but stomachaches could very well be related to high histamine levels. Diarrhea is extremely frequent in people who have elevated histamine levels. A simple blood test would reveal it. A histamine-free diet could relieve years of misery and reduce the need to ‘toilet map’ every time you go out. Results could be seen in as little as 3 weeks if you don’t cheat on the diet.

* Dermatographia. My son had this when he was young, and when I would scratch his back, thick raised lines would pop up on his skin.  I am homozygous for DAO, so I’m betting that he expresses the gene SNP even though I haven’t tested him. Persistent eczema is often tied to high blood histamine levels and all those expensive steroid creams won’t do you a bit of good unless you reduce histamine intake or improve tolerance. Supplements of DAO may help, I’ll tell you about that later.

* Vertigo and dizziness. This could result you going in for expensive MRIs to determine what is wrong, or rule out brain tumors. High histamine could be one simple cause though. Also vertigo and dizziness (and lightheadedness) are often associated with a condition called POTS which you can read about by clicking here.

* Abnormal or erratic menstrual cycles. Lowering histamine levels could make each month a little more comfortable and might result in you being able to avoid the drugs used to control PMS problems like expensive antidepressants and analgesics.

* Asthma. This category is HUGE. All the inhalers needed, and the fear associated with bronchospasm. It can be fatal of course. What if reducing histamine helped you, can you imagine how much better your life would be?!

* Core body temperature.  Histamine impacts your body temperature via two different mechanisms. It will cause it to drop below normal. How many of you are told you are hypothyroid when it is really histamine intolerance and dysregulation, I wonder about that.

* Pain. Histamine intolerance leads to more pain, controlled by NSAIDs, acetaminophen or opiate pain-killers. Do you have chronic fatigue or fibromyalgia that is unresponsive to typical medications that should help? Consider histamine elevations. Pain syndromes are often treated with NSAIDS.  Aspirin, ibuprofen, naproxen and other NSAIDS are known to cause elevations in histamine. So do other pain killers like the opiates (oxycodone, hydrocodone, etc). It’s definitely a conundrum. I think if it were me, and I needed these medications (any of them) then I would consider low dose DAO supplementation, but that is just me. I cannot advise what is right for you, okay, so have a candid discussion with your physician.

* Multiple Sclerosis (MS) and other Autoimmune diseases. Histamine is a crucial factor for both the initiation and maintenance of painful inflammatory disorders of the CNS (central nervous system). A 2013 study confirmed that the cerebrospinal fluid of patients with MS held much higher levels of histamine than normal participants.

* Hypertension. Blood pressure will rise in the presence of high histamine. Millions, no billions are spent in this country on anti-hypertensive agents, not to mention the cardiovascular complications that result from uncontrolled hypertension.

MTHFR and Histamine

Having the MTHFR mutation doesn’t necessarily mean you have a methylation defect, but it does raise your risk. I think most people with the mutation do have a methylation problem, but that is just my opinion.

Histamine isn’t a bad guy, it’s needed to create stomach acid and to perfect your gut motility so that you can get food through you properly. DAO or “diamine oxidase” is an enzyme that is outside the cell (termed “extracellular”) and it breaks down histamine in the intestinal tract. 

Foods and drinks can be high histamine such as wine or other alcohol, seafood, citrus fruits, berries, chocolate and leftovers that may have begun fermenting. In fact,  fermented foods and leftovers are very high in histamine, and when you eat that you have to have enough DAO enzyme on board to break down that histamine. A SNP in your DAO gene will hinder that process and cause histamine to build up in your bloodstream.

High histamine is prevalent and often undetected. It can lead to chronic inflammatory conditions. You see it frequently in skin disorders such as eczema, unexplained skin rashes, itchiness, hives or increased sweating.  Intolerance to alcohol is another clue. High histamine predisposes you to nausea and feeling woozy or developing sea sickness.

Reducing high histamine foods can help, as can taking DAO supplements to help you deal with a polymorphism in your DAO enzyme.  The supplements will help you deal with all that bloodstream (extracellular) histamine.  If you don’t take care of mitochondria, and have enough glutathione, the histamine levels will also rise. This causes a lot of inflammation. It’s unfortunate but inflammation runs rampant as cytokines build up in our body, histamine being one of them. It makes you chronically ill and no matter what you do, nothing will help until you reduce histamine.

You may be sitting there thinking, “Fine I’ll just stop eating cheese and drinking wine” but it’s not that simple. The consumption of high histamine foods/beverages is just one simple scenario, and the plot thickens if you have a DAO SNP because then it’s like a one-two punch because you are eating histamine (first punch), yet you can’t break it down (second punch).

My plan for you would be as follows, and not necessarily in this order: 

1) If you have a chronic illness, I would test your blood levels of histamine, ask your doctor to order the test. Any physician can do this. If for some strange reason, you can’t make it happen easily, go ahead and order the test by yourself. Since I am a practitioner with Direct Labs, you can go through my private link by clicking here.

2) Realize histamine plays a role if you have chronic skin conditions, it is almost a given! For example, if you suffer with eczema, psoriasis, other skin rashes, hives, wheels or itchy bumps it is almost always tied to high histamine or a DAO block (like a SNP).  Realizing this puts you on the fast track to wellness. Almost as important are lung concerns like wheezing, chronic sinusitis, asthma and the sniffles.

3) Consider supplementation of DAO, sold nationwide and at many health food stores.

4) If you have hypothyroidism, or Hashimoto’s thyroiditis or Graves’ or any other auto-immune disorder such as Multiple Sclerosis, there is evidence to suggest lowering histamine can help you so I would eat a low-histamine diet, not a high one (this means no more histamine-containing foods, and no more histamine-producing foods). Many of these are fermented foods often mistakenly suggested to improve gut microbiome. You should be doing that with healthy probiotics and/or healthy yeast (ie Saccharomyces boulardii).

5) DAO is over-the-counter, but I don’t recommend self-treatment, and I can’t personally advise you. So even though you can buy these supplements anywhere, it’s always a good  idea to talk to your physician about using DAO instead of antihistamines. This is crucial for serious conditions like asthma, do NOT (repeat do NOT) go off your steroids and inhalers, as these may still be needed for your total recovery. DAO supplements are derived from pigs, in case you have allergies. DAO enzymes will dry you out, just like antihistamines. Some supplements are super strong, and some are mild, you’ll have to choose what you like as I cannot advise you. But do have a candid and open discussion about the possibility of histamine intolerance, and how it may apply to you.  

I know that I will be asked about dosages. It varies and you should use the lowest effective dose. Some of you can take a capsule just before eating a meal that is high in histamine and some of you need daily support. The dose varies, some of you may need half a capsule, others may need 1 or 2 capsules (20,000 to 40,000 HDU) taken daily.  
DAO supplements are usually taken before a meal, however, there are no hard fast rules.  Follow (or adapt) the directions stated on the label of the product that you purchase.

6) Consider the herb HOPS (follow label directions) to reduce histamine levels.

7) Consider quercetin (about 250 to 500 mg taken three times daily) in order to reduce histamine levels. This bioflavonoid is okay for people with normal or low dopamine, but not high dopamine as it will exacerbate that.

8) Avoid fermented beverages like wine, champagne, beer and kefir. Avoid fermented foods too like cheese, yogurt and sauerkraut. Remember fermented foods are high in histamine.

9) Go on a histamine-free diet and avoid the following:
Farmed seafood, including shellfish
Smoked meats
Fermented dairy products like buttermilk, yogurt, cheese of any sort, aged cheese, kefir
Citrus fruits
Dried fruits: Apricots, cherries, cranberries, prunes, currants, raisins and dates
Tomatoes and tomato sauce
Spinach (it’s high in oxalates anyway, so keep this to a minimum)
Vinegar-containing foods like salad dressing, pickles, relish, etc
Anything fake like a food additive (artificial colors, preservatives, benzoate’s)
Soy sauce or miso
Chocolate (boo hoo, sorry guys!)
Cola drinks 
Spices like cloves, cinnamon, chili and curry
There are other foods, this is not complete.

10) Feed your mitochondria if necessary, glutathione supplements may be critical for some of you. If you have poorly functioning mito, the histamine will be more apt to build up.

11) Look at your medication list to see if you are taking a medication that is causing a MIS (medication induced SNP). If you are interested in seriously cutting-edge information on genes, and how medications induce SNPs (and you have good understanding of pathways) you can check out my Keyring Pathways.

Finally, histamine travels throughout your blood, it is carried in the bloodstream, so histamine can affect  you anywhere, from your gut to your lungs, your brain, your heart, skin and central nervous system. Feel free to share your store and comments below. Keep in mind, I receive hundreds of questions and comments at this site each day and unfortunately I can’t answer them all. I’ll chime in as I can. Please help each other.



  1. Rita Rodi October 18, 2015 at 2:20 am - Reply

    I was intrigued by your recent article on Allergies and Your Genes. For the last six months+ I have been experiencing skin problems that I have never had in my 58 years. I have not changed any products or anything like that. I have been getting this dry itchy patches that have popped up on my neck, chin, cheeks and now my eyelid. They come and they go. The dermo hasn’t determined the cause yet. She prescribed changing face washes, no pefumes, Cera-ve lotions. No success. She put me on doxycycline and metronidazole–no changes.

    The hydrocortisone creme is the only thing that has worked so far. I use it, the patches go away, only to return in another 10-14 days. I have Hashimoto’s. I had no idea about the relationship between histamines and Hashimoto’s. I read the full article on your website and I am interested in ordering a test to check my histamine levels as you suggest as I eat many of the foods on the high histamine list. However, I cannot determine which test is the correct one for this purpose. Can you please point out which test would provide that information? Thank you very much for enlightening me.
    Rita Rodi

    • Suzy Cohen October 18, 2015 at 8:11 pm - Reply

      Hi Rita
      You can ask any physician to order the histamine test or by it yourself:
      (There are other tests that can evaluate allergies, such as those offered by Cyrex). I will now let a physician in our community continue with other tests, if they choose to do so.

      • russell October 24, 2015 at 2:38 pm - Reply

        Hi Suzy I too have a serious problem with the area around my eyes and nose,it blow’s up like rocky balboa then starts to itch and leak a clear yellowish fluid,finally it scabs up and peels,have been to several doctors but cant find a cure have to just let heal by itself sometimes a month or more,can’t go out in public its so bad.any suggestions?

  2. Susan October 18, 2015 at 11:03 pm - Reply

    Interesting article that I will need to study to fully comprehend!

    One question: When I first started having health problems (diagnosed as fibromyalgia, hypothyroid at that time) I suddenly became intolerant of milk products and also unable take antihistamines. The antihistamines cause intense pain all over my body so I avoid them at all costs. Could this reaction be related to the information in your article?

    Your food list has a lot of similarities to the autoimmune protocol diet. Another avenue for me to explore.

    • Suzy Cohen October 19, 2015 at 10:44 pm - Reply

      I don’t know for sure honestly.

    • Shasha October 21, 2015 at 2:56 am - Reply

      I need no gluten/dairy/soy/sugar/GMO…vitamins/good oils/minerals…probiotic….LDN..detoxing. Gluten may cause antibodies to the thyroid. People who can’t have gluten may not be able to have dairy. Lactose intolerance is when the tips of the villi that make lactase are hurt. When a person eats 100% no gluten..then the villi tips heal and make lactase again to digest lactose. My dairy issues are casein or the fat which hurts me. Fibromyalgia….cells are making lactic acid since they are low in oxygen due to low thyroid and gluten can hurt intestines so less nutrients absorb..then cells are not made right to work right and are low in oxygen burning and instead make lactic acid. I can’t take extra niacin…flush too much. I have MS due to low thyroid/heavy metals/Celiac etc. Th2 foods may cause swelling also. They stimulate the immune system to make antibodies. Se may lower antibodies to the thyroid. Vit C may lower histamine. Too much Vit C may hurt. Zinc raises histamine. Zinc helps the thyroid, but Cu/Zn need to be more balanced. Hair tests show good mineral and heavy metal levels. Far Infrared Sauna may help detox heavy metals/chemicals/yeast/bacteria/Lyme etc, but then good minerals need to be restored since good minerals are also lost in the sweat. Best wishes.

    • Susan October 26, 2015 at 10:17 pm - Reply

      This exact same thing happened to me with the dairy! I’m not sure about the antihistamines, however several other prescription medications (cymbalta and allopurinol) made me extremely ill after about 3 days. I could always eat, drink and take anything before the thyroid and fibro. Very interesting…!

  3. Karen Slama October 21, 2015 at 1:52 am - Reply

    In your article on Allergies and Genes, you mentioned DAO SNPs, you explained what DAO is, although it wasn’t easy to understand, but what is SNP? I have year round allergies, so was very interested in this article.

    • Suzy Cohen October 21, 2015 at 3:16 am - Reply

      A SNP stands for Single Nucleotide Polymorphism, it’s kind of like a speed bump on your DNA that either upregulates (speeds up) or downregulates (shuts down) a metabolic pathway. SNPs don’t do this for sure, they are merely potentials. A SNP may never even express itself. A person with a DAO SNP that is expressing, may be more prone to food allergies. If you’d like to read more on SNPs, you can put that in my search box, I’ve written articles about other important SNPs such as those pertaining to methylation. If you have a few minutes please read that.

  4. Jane October 21, 2015 at 2:05 am - Reply

    Thank you Suzy for the wonderful contribution you make in helping people heal.
    Many Blessings

  5. Angie October 21, 2015 at 2:14 am - Reply

    I read your article and found it very informative. I suffer from many allergies all year round, and I cannot take antihistamines of which I am allergic of also I break out in a severe and painful rash so I have to suffer from my allergies. What would you recommend. I also have an underactive thyroid and COPD.

  6. Angela October 21, 2015 at 2:16 am - Reply

    I am very interested in the article you wrote.. I can tell you I don’t understand it totally, but will digest it and learn from it. I have a 13 year old son with asthma. He is fairly non symptomatic. However, he has a low lung capacity, 75% for FEV1 and 54% for the lower airways. We have had him on several inhalers to raise the numbers, however they only bring it up to 85% range. We have tried zantac and no improvement. We are now on to Fish oil pills and probiotics. He is allergic to dust mites and tree pollen. However he is running cross country and playing basketball. For the most part we are just treating a number. Do you have any suggestions? Would the genetic testing you talked about be helpful to figure out what is triggering the low low capacity?

    • Suzy Cohen October 21, 2015 at 3:26 am - Reply

      I don’t know a lot about it but one thing for sure, when we took the kids off dairy (100% off dairy, all of it) they all got better, many went off their inhalers- this was in the hospital that I worked in many years ago. Sometimes within 2 weeks. You can see if he’s interested in that. If he’s running cross country and playing basketball that’s a good sign!

  7. Leah October 21, 2015 at 2:29 am - Reply

    This is a great post. Thank you! What are your thoughts about a histamine test that came back low with high DAO but definitely symptomatic (with hashi, including large nodules and goiter, relatively normal labs apart from low free t3 and high tpo,Candida, mold, allergies and some chronic viral problems, hysterectomy at 45 due to constant bleeding and pain). Mother has definite histamine issues along with dermatographia and father had MS and the whole family has allergies eczema asthma and other “autoimmune” issues that include anaphalaxis. I have all sorts of mutations and I believe some that you mention. But how could test results basically be reversed? And yes I was just considering going on GAPS. All so confusing.
    Thank you Suzy!

    • Suzy Cohen October 21, 2015 at 3:30 am - Reply

      This is just A LOT it requires a doctor. It confuses me too.

  8. Sherri October 21, 2015 at 2:58 am - Reply

    Just a quick thank you to say I appreciate all you do to help others! I know I get so much from your articles. I have tried so much in search of “feeling good”! Not sure if I have the snp or not but I’m going to do my best to try low histamine and see how I do. I’m compound hetero mthfr and have hypothyroidism. Hmmm or do I ?
    Thanks again!!!

  9. MIKE BOWMAN October 21, 2015 at 3:09 am - Reply

    HI SUZY, I started getting an irritation over myair way back in august that soon got worse and turned into a bad cough and sinisitis. One doctor said it was hay fever and put me on a steriodal and alegra two times a day.Well it got even worse with chronic cough and I seen another doctor who said I had walking phnemoia and put me on anti biotics. It got better but Im still having bouts with coughing and sinus runny nose till this very moment. I’m still taking allegra every day. Sorry for the bad spelling.Could this be to high histamine.

    • Suzy Cohen October 21, 2015 at 3:13 am - Reply

      It could be but it sounds like infection, you need a REALLY GOOD doctor not self-treatment.

    • Arvilla October 21, 2015 at 7:58 pm - Reply

      Hello Mike,

      After reading your detail, I have some thoughts that may be helpful to your investigation.

      First, when we know that environmentally-acquired bacteria opportunistically enters the Respiratory system to infect the lungs, there is also risk of this same pathogen moving into sinuses. Thus, for the first MD to put you on a steroid…the reason you “got even worse with chronic cough” was because the steroid was/is immune suppressive or, not immune enhancing…which, in turn, allowed that infection to ‘better’ thrive.

      Then, while I don’t know if this was via clinical exam or confirmed by blood test, for the second MD to say you are dealing with “walking pneumonia” this is often about a very small, but injurious bacteria known as Mycoplasma pneumoniae…which you can test for, even at Suzy’s preferred Direct Labs or Life Extension ( and if caught early, a certain class of antibiotics can be effective, but even though you did enjoy that brief improvement, it sounds like you’re back to dealing with earlier, now chronic, symptoms.

      Thus, rather than for long lingering cough and runny nose (both indicate inflammatory irritation, attempt to expel) to be about excessive histamine, I am inclined to think that after using that Anti-biotic (even if for only 10 days), there is likely to now be an imbalance in your digestive track/gut after this non-discriminatory drug not only killed off the ‘bad’ micro-organisms, but so did it annihilate those of the ‘good’ (protective) variety. And to restore this imbalance by recolonizing or building up your stores of microbacteria, you will need to use a high dose/high quality, Pro-biotic (which, btw, means…’for life’).

      Most MD’s who prescribe the antibiotics do not know to tell their patient they should be sure to use a ‘follow-up probiotic’ for this important restoration. At the same time, you might look into a product I have used both safely and successfully that is called Air-Power and sold by Enzymatic Therapy. By primary ingredient, it is a ‘guaifenisen expectorant’ that ‘helps to thin and loosen mucus’ and ‘clears respiratory airways’ and ‘make coughs more productive.’ (Although there is an OTC product for stuffiness of (supposed) allergy that contains guaifenisen, I cannot think of its name right now, but in this other, the dose is 200 mg so you do want to compare or, not buy if less.)

      So, after all this said…which is to offer you hints on how to repair or shore up the innate immune system (make more robust) and maybe lessen those adverse symptoms, I totally agree with our fearless leader Suzy in so far as your primary (underlying) issue as being about (still) unresolved “infection.”

      For what it’s worth, I would next investigate to know the blood level of M. pneumonae bacteria because this is often a co-infection of Lyme disease which is not only incited by tick bites, but so can it be shared via the insect vectors of mosquitoes and fleas. And when you say these symptoms started “back in Aug” it makes me wonder where you live in the country and whether you were camping or doing other sustained activity in the great outdoors.

      As I’m sure you realize, “walking pneumonia” is nothing to mess with for the long haul (especially as we get older) and so, rather than turn to the typical suppression or short lived improvement of drugs, I agree: your best tact is to find, as Suzy says, “a REALLY GOOD (integrative, functional, orthomolecular, maybe LLMD) doctor” to put this challenge behind you.

      All best wishes for your soon restoration. 🙂

  10. lori October 21, 2015 at 3:38 am - Reply

    I went to the direct labs link what is the name of the test for histimine levels? Thanks

    • Suzy Cohen October 21, 2015 at 4:04 am - Reply

      “Histamine determination, whole blood”
      You take the kit to any local lab. I do think a doc has to sign off on the requisition, but I’ve never in 10 years heard of a doc refusing their patient a signature.

      • Helen October 21, 2015 at 7:52 pm - Reply

        That particular test is not on the list.

        • Adriane October 23, 2015 at 3:22 am - Reply


          When you are on her page at Direct Labs (the link she provided above), type Histamine in the search box and then hit the search tab and the test will come up.

        • Laura October 23, 2015 at 8:45 pm - Reply

          That test is not listed as an option. Help 🙂

  11. Elaine October 21, 2015 at 3:45 am - Reply

    Hi Suzy, I always love your work. Your article lists many important points but you do not list the DAO snps. I have many genetic reports made from my 23andMe data and in one of them they list 6 DAO snps. Three of mine are -/- and three are +/-. So I have 3 variants, one each in 3 different DAO snps. What DAO snp are you talking about in your article please. I don’t seem to have any problems with histamines but have not been tested. I have taken the equate nighttime sleep aid every night for about 25 years due to hot flashes so I can get some sleep and these have 25 mg of Diphenhydramine which I think is an antihistimine, correct? Maybe that is why I have no problems at age 65. Thanks for your reply.

    • Suzy Cohen October 21, 2015 at 4:01 am - Reply

      Hi Elaine
      I don’t want to get into specific rs IDs, look at them as a whole. Since you have 3 +/- (heterozygous) of a total of 6, I would say there is the possibility of it expressing and as you (simply put) having a SNP and showing signs of histamine intolerance.

      • Elaine October 21, 2015 at 4:51 pm - Reply

        Thank you Suzy. I am curious why you think I am showing a histamine intolerance. Because I have hot flashes at age 65? (because I know I shouldn’t be having them since age 40 but just assume it’s hormones which I refuse to supplement). I love your Drug Muggers book BTW. These nighttime sleep aids are the only drug I take!

  12. Issie October 21, 2015 at 4:13 am - Reply

    Great article Suzy!

    A few suggestions that work for me (I have MCAS – Mast Cell Activation Syndrome), for people who have issues with rashes or itching and it’s mast cell related —- I use, NasalCrom in an unscented cream and/or with a carrier oil and use externally on skin where needed. It helps the itching. I have at times used hydrocortisone cream and use the two together – when necessary.

    I use the traditional mast cell antihistamines – the ones that work best for me are Allegra and 1/2 of a Zantac (more makes stomach hurt). Allegra is the only H1 blocker that doesn’t affect my cognitive function adversely or cause me to be tired or sleepy. I had to add a mast cell stabilizers to these as this wasn’t enough. In the USA the one that most of us use is GastroCrom. When I added this I started to improve. I also have HYPERPOTS and that also got much better with this RX addition. Some others use Ketitofin and find it helpful. There are some who also add an H3 Like Singular. I personally don’t do well with that one.

    NasalCrom is a much weaker version of the oral GastroCrom. It is over the counter.

    For the person having issues with the antihistamines – some have issues with dyes and fillers. We just keep trying until we find what we don’t seem to react adversely too. It may also be possible to have it compounded. (I’ll let Suzy talk about this.)

    There are some controlling their MCAS reactions with the foods they eat and supplements.

    With mast cell issues, one thing of interest – hot flashes that aren’t connected to hormones. My hubby knows before me when one is coming. He can feel my skin change. I feel it with a headache that gradually intensifies. I keep children’s Allegra handy for the ones that get really bad and need a quick response. So far, I’ve not had to use an epipen, but I do have one. I did have an emergency room visit once when it attacked me at heart level. It’s called Kounis Syndrome and strongly resembles a heart attack. Treatment is high doses of antihistamines and nitroglycerin. Scares the docs when the nitro helps – but thankfully there is no heart muscle damage. (Word of caution – this was triggered by chewing too much gum with aspartame in it. High levels of glutamate can trigger an attack.)


  13. Perry October 21, 2015 at 4:15 am - Reply

    Suzy, you are a rockstar. Excellent work putting this all together!

    Three topics come to mind that i hope you can comment anything on:

    1) Where is an accurate list of histamine foods? The internet has a thousand different ones.

    2) Any comments on how this physical challenge overlaps/interfaces with “pyroluria” (Nora Gedgaudas has an article here: For example, I always feel bad when I take fish oil. Seems to me that my reaction could be from either, or even both issues: 1) if in fact fish oil is a histamine-triggering food…OR, I’m one of the people that needs more healthy forms of Omega 6, instead of Omega 3 (i.e. fish oils).

    3) I’ve been subscribed to the work of Yasmina Ykelenstam “The Low Histamine Chef” and see she’s got a list of mast cell tests ( Any comments on the validity or usefulness of any of those in diagnosing this disorder, beyond just the testing you mentioned?

    Keep up the excellent work!!! Much appreciated.


  14. Jennifer October 21, 2015 at 4:20 am - Reply

    Hi Suzy,

    First of all, I’m your biggest fan! I’m a dental hygienist and I tell my patients about your “Drug Muggers” book all the time! My friends and family, too.
    I’ve been dealing with weird, annoying and uncomfortable symptoms for 10 years now. They include eye irritation, dizziness/vertigo, GI troubles, anxiety, fatigue and insomnia. I cannot tolerate alcohol anymore. I have a mild burning sensation in my mouth. I have had some minor and major sneezing and runny nose episodes out of the blue. These symptoms developed over time. I’ve seen many conventional doctors and nobody cares to find the root cause, they only want to write me Rx’s or ship me off to another specialist. I don’t trust the conventional system! I’ve been paralyzed by money issues and insurance that won’t allow me to see a functional medicine doctor just yet. I’ve done lots of my own research and started taking many supplements to reduce inflammation, promote GI health and reduce nutritional deficiencies, increase stomach acid with HCL and take enzymes and antioxidants. I know I sound like a crazy person. But I’m not! This article speaks to me on several levels. What would be your plan of attack for my situation?

    Thank you. I think you’re a genius?!

    • Suzy Cohen October 21, 2015 at 5:25 am - Reply

      You don’t sound crazy to me. It’s sad that no one in 10 years has run the right tests and they’ve just spent your money. I don’t know what to say other than I think health begins in the GI tract. And if that is intact, and you’re still sick/uncomfortable, then I start to think undiagnosed infection or overgrowth or colonization of organisms. this will start the cascade of inflammation and hormone disruption. I think one of those 23andme tests would be helpful in time, and a GI Effects stool test. You’ll never fix it if you don’t know what’s broke. (Thank you for your kind words) and the work you do to make others pretty and confident about their smile 🙂

  15. Lois Thompson October 21, 2015 at 5:53 am - Reply

    If you want to use food instead of DAO pills that have additives sensitive people have problems with, then you can use sprouts from any legume grown for 7-10 days grown in the dark (stress increases DAO production in the sprouts) and put in a smoothie or salad dressing to make it more available. Try eating the sprout smoothie and see what it does to your symptoms. You can do a blood test but if you do the food challenge you know if adding the enzyme works. You can try staying off histamine foods first. We have like a certain amount of histamine we can tolerate and then our “bucket” is full and starts to overflow and then the symptoms show up. That is why it is hard to pick up on this. Put some of the histamine foods back in and Then try the DAO challenge especially if you know you have the snps and see if the sprout smoothie relieves you symptoms. If you need help sprouting that happens to be one of my expertises. I am the sprout consultant at Mumm’s Sprouting Seeds. [email protected]…/

  16. Lois Thompson October 21, 2015 at 5:55 am - Reply

    If you want to use food instead of DAO pills that have additives sensitive people have problems with, then you can use sprouts from any legume grown for 7-10 days grown in the dark (stress increases DAO production in the sprouts) and put in a smoothie or salad dressing to make it more available. Try eating the sprout smoothie and see what it does to your symptoms. You can do a blood test but if you do the food challenge you know if adding the enzyme works. You can try staying off histamine foods first. We have like a certain amount of histamine we can tolerate and then our “bucket” is full and starts to overflow and then the symptoms show up. That is why it is hard to pick up on this. Put some of the histamine foods back in and Then try the DAO challenge especially if you know you have the snps and see if the sprout smoothie relieves you symptoms. If you need help sprouting that happens to be one of my expertises. I am the sprout consultant at Mumm’s Sprouting Seeds. [email protected]…/

  17. Bob T. October 21, 2015 at 6:18 am - Reply

    An interesting post and very informative. Something in what you wrote rang a bell of sorts and I am not sure I can put my finger on it hence a thought or two and maybe a question as I am thinking out loud. I have read somewhere on one of your web pages a while ago that your husband had/has Lyme disease. I live in Boulder CO where it is not endemic so I am sure I picked it up elsewhere sometime in the 80’s when I first got sick. It went diagnosed until 2010 and by then I was so ill with so many symptoms I was barely able to walk. The ELISA and Western Blot tests always came back negative when I requested them. Finally after sending my own blood to labs I found online was I able to discover what was going on. I had Lyme disease, babesia, bartonella, rickettsia, and a host of opportunistic infections that included parasites, viruses, as well as fungus. Subsequently I spent over 2 1/2 years on various antibiotics along with other medicines. I also followed various herbal protocols both western such as Stephen Buhner’s and TCM when the antibiotics never really did the whole trick. Whenever I increased the dosage of whatever I was taking be it antibiotics or herbs I got a Herxheimer reaction that was severe and unbearable so it was slow going but I did improve considerably. During the last 9 months or so my symptoms began returning ala Dr. Horowitz’s book “Why Can’t I get better……etc.” bringing me to this. If your husband has/had Lyme during whatever treatment regimen he followed did he happen to get a Herxhemier reaction and if so does he also suffer from allergies and has he gotten over Lyme and is now symptom free? I have always had a predisposition for allergies, hay fever and irritable bowel and I also had Dermatographia as a kid and I am wondering if some of my ongoing symptoms could have their roots in elevated histamine levels and whether they are playing a part in exacerbating the Herxheimer reaction. Interestingly, as the Lyme and its cohorts slowly got the upper hand while my health spiraled downhill my allergies waned. Whether that was due to suppression of my immune response by the Lyme or something else altogether there is some connection. I have not had my histamine levels tested but I will do so in conjunction with my CD57 levels to see if they might be inversely related. Anyway, just wondering. Glutathione among other things such as Alpha Lipoic Acid are also used to ameliorate the Herxheimer reaction as is B6. Is it histamine? Does die off cause histamine release hence the Herx? ???????

  18. Marja October 21, 2015 at 7:53 am - Reply

    Oh my. I apparently have Hashimoto’s and I do have some sort of histamine intolerance, I cannot tolerate tomato, strawberries, kiwis, chocolate, dairy and so on, banana is the worst, makes me so ill.

    I usually end up having hives, or feeling wobbly, nausea etc. But this summer I developed nasty cough after eating strawberries and having some tomato in sauce. I feel like choking and my lungs are wheezing. It resolved after skipping strawberries and tomato.

    I do have lack of certain strains of bacteria based on stool test, not over growth of any. I am missing e.coli, lactobacillus, and something called enterococcaeae (?). I am currently taking multi-billion dophilus which seems to help a bit.

    Also my eosonophil % count is slightly high (range 1-6%) 9%, that was considered high because I just had bad episode of hives before blood test. Was the only thing doctor admitted can have something to do with some sort of allergy, no other test done.

    I have been ill for 15 years, feeling awful and sick with low temperature. It has been just awful. It all started after long period of using antibiotics 20 years ago. Never recovered, strong PPI’s made it worse. Not a day I have felt good ever since. I never feel normal and I have no appetite. I am not getting any help and not on any medication even though for example my t3 is low.

    The interesting thing is that my dad has really bad psoriasis, and my big brother was just diagnosed having cluster headache! That would be a good reason to get some more tests as this could be some mutation we inherited? Over here in Finland doctors do not seem to know much about these issues.

  19. Carol Shelton October 21, 2015 at 8:20 am - Reply

    I sent this article to my doc. I, too, have an unusual story and have been seeking a fix for the past several years. I am almost there!

    I, too, share your work with my patients on the Med-Surg floor I work on. I keep copies and let interested patients take a gander at the material! Drug Muggers has especially been a favorite…also your book on diabetes is great for the newly diagnosed type 2.

  20. wes October 21, 2015 at 10:18 am - Reply

    You could call it a MISNP, like a mis-step.

  21. Diane October 21, 2015 at 11:40 am - Reply

    Very informative article Suzy. I have an 18month old grand daughter who has extreme eczema. Watching for food sensitivities and a good probiotic has helped, but her hands always look so red and raw. Would you approach histamines the same with a young child?

  22. Robin October 21, 2015 at 12:39 pm - Reply

    I’ve seen much more restrictive lists and diets for histamine intolerance that basically eliminate most meat and are semi-vegetarian. Do you disagree with this?

    I’ve had chronic allergies year round all my life, including mild asthma and atopic dermatitis. (The latter got better when I started taking methylcobalamine. Now I know it’s the extra methyl groups.)

    The problem is that I also have to watch my blood sugar which is also a bit high, so I can’t eat too many carbohydrates. (Not to mention fructose malabsorption and Hashimotos) However, extremely low carb gives me low blood sugar symptoms. (This limits me to meat, greens, low sugar fruits like tomatoes & a little starch with blue corn/potatoes, etc to compensate for practically no fruit )

    Now, if I add the histamine intolerance diet on top of this, especially the more restrictive ones, there’s almost nothing left that’s OK for me to eat. Just about any protein would have histamine in it. Even your less restrictive version cuts out some of the few fruits/vegetables I have left like tomatoes & spinach. What about eggplant & pumpkin, which are also supposed to be high in histamine?

    So what do I do now? If I follow all the rules, there’s almost nothing left I’m supposed to eat. Cucumbers anyone? 🙂

  23. Susan October 21, 2015 at 1:14 pm - Reply

    There is no test on direct labs listed on that page with that name – please check it out yourself.

    • Suzy Cohen October 21, 2015 at 5:01 pm - Reply

      I was just there. Put histamine in the search box, maybe that way.

  24. Carrie October 21, 2015 at 1:26 pm - Reply

    Hi! I have been tested and do need the DAO enzyme, but I am allergic to pig and pig products.
    Can you recommend a product or two, that would work just as well? I thought that something like Quercetin simply goes in,’after the fact’ and helps with the symptoms. What are some good non-pig formulas? 🙂

    • Suzy Cohen October 21, 2015 at 5:06 pm - Reply

      DAO only comes from pigs.
      Have you tried putting “allergies” or “quercetin” in my search box? I’ve talked about this in other allergy articles.

  25. Nicole October 21, 2015 at 1:44 pm - Reply

    I have a question regarding fermented foods, if they are cooked does that reduce the histamines to an acceptable level? I know that kills the beneficial bacteria, so how can you get the bacteria in your gut outside of fermented foods? Thank you.

  26. Tamie October 21, 2015 at 2:13 pm - Reply

    Dear Suzy,

    Thank you for this very interesting article.

    I’ve been suffering since 20 years now, from a skin reaction to water (shower, perspiration and humidity). The crises happen in general after the summertime, September to December, and their intensities depend on the year and on the day time. They are stronger in the morning. I’ve seen many conventional generalists and dermatologists but they didn’t help me and couldn’t explain what was happening. One advised me to take antihistaminic everyday, which I tried for two days but I didn’t feel it was working and since I didn’t want to take antihistaminic everyday, for my whole life, I immediately stopped it. Intuitively, I was feeling, coffee, wine and cheese the cause of my problem.

    Since 3 years now, I’ve been seeing a holistic doctor and she discovered Hashimoto hypothyroiditis along with a leaky gut condition. So since, I am following a strict diet without gluten and dairies and supplementing with probiotics, Vit B12, Spirulina, Magnesium, Coq10 and Cod liver oil. For two years I did not have any crisis (Youhou !! I could enjoy taking a shower without crying !). But this year, I am having the crises again.

    The differences with previous years are that I stopped all supplements during the summer, I had some (many) diet exceptions, a lot more of coffee and wine, and started taking water kefir and fermented foods.

    Please Suzy, what do you advise me ? I feel Vit B12 helps me and also magnesium.

    Thank you and all the best for you,

  27. Jann October 21, 2015 at 2:41 pm - Reply

    ‘Request a Test’ website has the ‘histamine intolerance’ test [$129]… and doesn’t require a doctor to “sign off”.

    You’ll get a LabCorp lab request sheet that you take to your local lab draw center. They email you the results.

    • Suzy Cohen October 21, 2015 at 5:00 pm - Reply

      Oh thanks Jann, maybe it is that way with Direct Labs. Those labs are all kind of the same, and regulated by the same Internet laws.

  28. Patt October 21, 2015 at 3:07 pm - Reply

    Hi Suzy,

    You are a great health resource and I read this blog with great interest and some dismay. But, it may prove very helpful if I can give up a lot of the histamine producing foods in my diet. I was diagnosed 30 years ago with fibromyalgia and chronic fatigue, which finally culminated in a diagnosis of Lyme disease a year and a half ago. The Lyme specialist felt it was Lyme all along. I was on antibiotics for five months and was too worried about their eventual side effects so started pursuing alternative treatments. My current issue is widespread psoriasis and that is why your article is so interesting to me. I did find some connection in medical literature about tetracyclines causing psoriasis in susceptible individuals and that may be the case, but I don’t want to go on any of the conventional medical treatments for it. At any rate, I show four DAO SNPs, three of which are -/- but DAO A14747C is +/+. I am also heterozygous for MTHFR C677T. I am going to start the antihistamine diet (really, no chocolate?) and am wondering what your recommendation would be for vitamin B supplementation and glutathione. Also, is there anything else I can do to support my natural production of glutathione? Thanks for any observations and bless you for your research and work in these areas.

    • Suzy Cohen October 21, 2015 at 5:08 pm - Reply

      I wrote an article on glutathione recently, please put that in my search box. Also there are 480 articles or more here at my website (archived), you can find the answer to pretty much everything 😉

    • Suzy Cohen October 21, 2015 at 5:09 pm - Reply

      I wrote an article on glutathione recently, please put that in my search box. Also there are 480 articles or more here at my website (archived).

  29. Vanessa October 21, 2015 at 3:12 pm - Reply

    Could this cause a severe backache? I also have burning, itchy skin, and more foggy headed. I have been doing a detox for two weeks which includes drinking apple cider vinegar, bottled lemon juice, cayenne, and coconut water twice daily. My back hurts so badly from under the shoulder blades to lower back for no explicable reason. And it feels muscular in nature. I also stopped drinking wine at the beginning of the detox, and eat very clean.

    Thank you for any feedback.

  30. Pat October 21, 2015 at 3:21 pm - Reply

    Eye opening article. Quick question for the blood draw test. Can it be done anytime or only when you are experiencing symptoms like face flushing or burning etc. if you are not experiencing symptoms, wouldn’t that result in a negative test. Thanks ?

  31. lynn October 21, 2015 at 4:09 pm - Reply

    Hello Suzy,
    I have suffered from severe bed ridden cfs for 30 years. I recently started taking l-histidine for allergies to salycilates cats,,,etc. It really helped me and I also noticed my hair quit falling out. I upped my dose and took it for about a month and was so excited especially about he hair since I am a woman and it has been thinning throughout this illness. I noticed over the month that I became very depressed and then a few days ago started to itch all over. I believe I was low in it from suffering from allergies for years and then probably after supplementing for over a month got too much. I am going to resume taking it when the itching and depression lifts. I was wondering how this would relate to your theory. I have had my genes tested though 23and me but do not know how to retrieve the info. Do you personally take on clients? Thank you for the fabulous article.

  32. Brenda October 21, 2015 at 7:18 pm - Reply

    Thank you for all your work. I got the information to late to save my health but I do believe it may have saved my life. Bless you.

  33. Brenda October 21, 2015 at 7:19 pm - Reply

    What about Provigil (modafinil) ? I have learned so much from your work and others. Estrogen dominance and frequent rupturing ovarian cysts was treated with high dose Depo-Provera. For 10 years. At about 8 years the sleepiness got really bad, so expensive sleep study showed Idiopathic narcolepsy. Hence high doses of Provigil. Setting a body for a crash from mold exposure with HLA genes that don’t remove the toxins, and 3 rounds of antibiotics to treat a UTI. The last one being Levaquine. It is very sad that we simply trust our doctors even when they fail to listen to us. I reported many times that the Depo-Provera was causing excessive weight gain that could NOT be explained by diet or exercise. Dismissed as just lazy. Several months after Provigil I started developing all sorts of allergies to things that touched my skin. Even water at times would cause hives. I asked could this be related to Provigil and I was assured they could be no connection. After being put on Provigil ovarian cysts started rupturing at increased frequency. (I did not know that Provigil made Depo less effective.) My point is that our doctors are very ignorant about how drugs effect us. Now I never take a new medication without looking in my Drug Mugger book.

  34. Evelyn October 21, 2015 at 10:17 pm - Reply

    Thanks so much for your ALWAYS thought provoking article! Quick question..I have had major eye lense burning and irritation and I am wondering if histamine can cause that? It is so disruptive! I also have a mouth full of amalgams that I am wanting to remove, when I have enough money…could that cause it? Thanks again! Evelyn

    • Suzy Cohen October 22, 2015 at 7:05 pm - Reply

      You need an eye doctor. It’s not related to my article.

  35. Sue F. October 22, 2015 at 12:03 am - Reply

    I am at the allergist right now waiting for the dots on my pack to reveal themselves! FYI he told me shrimp makes a direct connection to histamine in your body. Some people get rashes may be getting histamine reaction but don’t have true antibody reaction! This happened to my son. He got a reaction but when we tested with the allergist shrimp prick it was negative but with real shrimp on his skin positive but then he isn’t actually allergic. The histamine came out in the skin after running after eating shrimp. Oral challenge produced no reaction though he’ll never eat shrimp and exercise after again. So guess what I have no allergy to the common molds and dusts nor dairy even though my ears mysteriously clog up after eating certain cheese or once it was grapes. So it must be a direct reaction perhaps from histamine in foods. The allergist says if it continues with that cheese that I could eat it with a scope in my nose to see if my estachian tubes close up. I’ll see about that!

  36. Ellen October 22, 2015 at 2:13 am - Reply

    I’m curious about histamine intolerance and allergy shots. Would that low dose of specific allergens work as expected and increase your tolerance or would it backfire and just increase your histamine level? I’m not asking about it as a treatment for HIT, just wondering if it would be likely to help seasonal allergies if someone suffers from HIT.

    • Suzy Cohen October 22, 2015 at 7:08 pm - Reply

      If you can’t break down histamine then those allergy testing shots will increase your histamine burden. Have to have a functional HNMT and DAO gene.

  37. Deedee October 22, 2015 at 2:37 am - Reply

    I take Zyrtec in the am and Benadryl and pm Im interested in taking the histamine test. Would I need to D/C my meds for any length of time before the test? I’ve tried the herbals before and they just don’t work for me. I hate to take them but really like breathing. I have asthma and I get miserable sinus headaches that lead to migraines when I don’t take the meds. I’m celiac and have many other things that go with it.
    Thank you for your informative articles.

    • Suzy Cohen October 22, 2015 at 7:03 pm - Reply

      DC for a week or two to see what your real levels are. Or, alternatively you can see how well your medications are working by taking the test while on them. It’s up to you, depends on what you’re seeking to know.

  38. Jenny October 22, 2015 at 8:25 am - Reply

    Thank you so much for the article. Leaves me in a real dilemma! I have Excema from birth, allergies to cats and horses from 14, herpes virus in eyes at 14, psoriasis at 14, (my parents divorced when I was 14!) now have non conversion of T4 to T3 at 47 although feel that has been happening for at least 7 years….. Self prescribe T3 which is really helping, healing my gut by staying away from Gluten, on 3,000mg of vitamin C, Glutathione, Probiotics, Vit B, Garlic, D3. Just wondered if I am on the right track?

  39. Pat October 22, 2015 at 3:23 pm - Reply

    Went to Requestatest site and they said to take the test when symptoms first appear. Can I still take it anytime? Don’t want to have a false negative. Thanks for this eye opening information. I am studying it, underlining it and living with it. Even have the 23 & me too. Thanks

  40. Eva October 22, 2015 at 6:31 pm - Reply

    Thank you, Suzy, for this great article!
    I did the 23and Me test and ran it through Nutrahacker who reports single nucleotide polymorphisms in the uploaded genome.
    I did find under the category: Neurotransmitter Levels one homozygous (rs701567) and one heterozygous (rs2391191) DAOA(D-amino acid oxidase activator) associated with cognitive manic symptoms. Does that have anything to do with the build-up of histamine levels or problems breaking it down?
    Thank you again for this great article!

  41. Ali October 22, 2015 at 11:07 pm - Reply

    I take Histame (1 4000 HDU capsule per meal) for mast cell activation disorder (extremely high chromagranin A and dermatographism, POTS, debilitating migraines, homozygous for the DAO SNP, and excessive sweating). I’ve taken this dose for a year but have not experienced improvements.

    I’ve noticed all the higher potency 20,000 HDU DAO formulations like those from Seeking Health or Swanson have corn starch and rice starch in them. I’m on the autoimmune paleo protocol however due to multiple autoimmune diseases (lupus, Hashimotos, Raynaud’s, celiac, interstitial cystitis) which omits all grains due to cross reactivity with gluten and other reasons. I also have pyroluria, chronic Lyme, and Ehlers Danlos type 3. Do you think the negligible amount of corn and rice would be worth it in order to take a higher potency DAO of the other brand? It would be way too expensive to take more capsules of the Histame brand.

    Also, what do you think about the DesBio homeopathic series for bartonella/babesia? Thanks so much for your help. I have hit serious roadblocks in improving my health and could really use the advice.

    • Suzy Cohen October 24, 2015 at 6:24 am - Reply

      Honestly I have no idea about the DesBio never heard of it. The rest of this requires a physician.

  42. Adriane October 23, 2015 at 4:08 am - Reply

    Thank you for this informative article!

    Are you including bio-identical hormones and natural dessicated thyroid hormones when you say that hormone replacement increases histamine? Or just the synthetic ones?

    Also, would taking a DAO supplement reduce production of stomach acid at all?

    • Suzy Cohen October 24, 2015 at 6:19 am - Reply

      Synthetic, not bioidentical. No not thyroid hormone. DAO won’t impact gastric acid.

  43. Cheyenne October 23, 2015 at 12:38 pm - Reply

    May be a dumb question, but if one can’t eat fermented foods because of having histamine problem, is it still okay for one to take probiotics?

    • Suzy Cohen October 24, 2015 at 6:17 am - Reply

      Not a dumb question at all, really good actually.
      Some people have trouble with probiotics for this reason, but most are okay. It’s very individual.

  44. Carol October 23, 2015 at 6:22 pm - Reply

    Thank you for the article. I have been dealing with Hashi, vestibular migraines, balance issues (vertigo, dizziness), stomach issues (I think I am becoming intolerant to dairy), my skin gets really red on my face and hot and sometimes my ears, I cannot find the trigger, though. I just feel like my body is not ever quite right. Could this be related to high histamine levels? What steps would you suggest I take?

    Thank you!

  45. Hazel October 24, 2015 at 3:49 pm - Reply

    Dear Suzy .I have Altroxin 0.5 ml Does that counthe as a drug mugger ?

  46. Cheryl October 24, 2015 at 5:38 pm - Reply

    Is Histame and HIst DAO considered DAO supplementation? Or histamine blockers? Same thing?

  47. Yasmina, The Low Histamine Chef October 24, 2015 at 8:49 pm - Reply

    Hello Suzy,

    What a wonderful post! I’m always excited when I see someone with a solid scientific background take an interest in histamine.

    I’d love to add one thing that I’m sure you’re already familiar with.

    While eliminating high histamine foods may be necessary for a few weeks in order to stabilise health, in the long term it’s rarely a good idea. I’ve seen in thousands of my readers that the food sensitivities continue to intensify, eventually causing reactions to previously safe low histamine foods. One theory proposed by several prominent mast cell/histamine specialists is that strangling the body’s supply of fresh histamine eventually causes a rebound effect as it increases endogenous release. It breaks my heart to receive daily emails from readers who are subsisting on just a handful of foods as they struggle to maintain the gains they made initially on the elimination diet.

    In my case, diagnosed with both histamine intolerance and mast cell activation, after limiting my diet for so long and becoming one of those with what I would now term a kind of orthorexia (at least in my case), I began experimenting with a diet rich in antihistamine and anti-inflammatory foods. My research into the condition in 2012 pointed me to the mast cell stabilising bioflavonoids you mentioned, putting them high on my list.

    I don’t disagree with eliminating low nutrient high histamine or junk foods, but experience has shown me and countless others that a sensible, balanced diet incorporating healthy generally anti-inflammatory foods is the way forward. Because as you know, mast cells don’t just house histamine but also prostaglandin, heparin, interleukins and leukotrienes (I’m over simplifying), so just focusing on histamine is not to see the wood for the trees so to speak.

    Thanks again for bringing your wonderful knowledge to the matter!

    All the best,

    The Low Histamine Chef

    • Suzy Cohen October 25, 2015 at 3:01 am - Reply

      Hi Yasmina, I’m a fan of your site and have mentioned it to others. Nice work!

      • yasmina, The Low Histamine Chef October 25, 2015 at 12:01 pm - Reply

        Hi Suzy,

        How exciting thank you!

        I would love to interview you for my site if you have time. I’ve interviewed a number of leading experts and would love to share your research and experiences with my readers.

        I’ll send you a request now.

  48. Pat October 24, 2015 at 10:27 pm - Reply

    If I have histamine problem, what strain of probiotic should be avoided. Which are the most problematic. Thanks Suzy ?

  49. Aimee October 25, 2015 at 3:17 am - Reply

    Hi Suzy,
    I read up on other natural antihistamine options beyond the DAO that you talked about. I read about vitamin c, bromelain, and stinging nettles….duh. All things I give my husband for his hay fever.

    In your opinion, do any of these supplements have the same level of effectiveness as the DAO?

    I have eliminated virtually all high histamine foods (with the help of a naturopath of course) unintentionally in an attempt to eliminate my sons chronic diarrhea. I had a food stats antibody assessment done on him and discovered that he is sensitive to a long list of foods. Despite patients and careful dieting, I cant seem to rid him of loose bowels although his growth has picked up again. I am suspicious that his body could be maintaining a high level of histamine. (I have long suspected he could have a few genetic SNPs as they run in my family along with spectrum disorders.) Thank you for all you share! I am learning so much from you!! Any other thoughts would be welcome. 🙂

    • Suzy Cohen October 25, 2015 at 6:35 am - Reply

      They’re not the same. DAO works as if your gene was working to create the protein/enzyme.

  50. Robyn Remnant October 25, 2015 at 1:00 pm - Reply

    Hi Suzy,

    My son has suffered from severe Migraines since he was 4 yrs to 28 yrs…He was put on Imitex and Imitrex injections at the age of 16. He takes Imitrex approx 3/4 times a week. Since he was a child he has had Exema and red ears on and off during the week. We have been to Head Pain clinics Allergy Drs. who put him on allergy shots he was put on anti depreesants and blood presure meds and is still on BP Meds with no change in his headaches. I believe he is getting rebound headaches from the meds… and I think it could be all related to Hi histamine after reading this article… He has recently been diagnosed with Hypothyroid and severely low Vit D levels. I would like to get a copy of your headache book for him.I will find on your site. THANK YOU FOR THIS ARTICLE…His quality of life has been so affected by his headaches and I am so worried about what the meds are doing to him in the long run.

    • Suzy Cohen October 25, 2015 at 5:20 pm - Reply

      It’s on the shop tab if you really want it. It could be extremely helpful because it connects the pieces, and lists all sorts of options. (You’re welcome).
      I have a 22 year old son, he used to get headaches as a little toddler, I think -looking back- it was the divorce stress combined with high histamine.

  51. Sheri October 26, 2015 at 11:40 am - Reply

    I, too, am wondering what could repair the gut if fermented foods aren’t good for those with high histamine. Have terrible anxiety and wonder if this could be cause. Suggestions for probiotics and other ways to heal gut? Thank you!

    • Suzy Cohen October 26, 2015 at 11:49 pm - Reply

      Hi Sheri
      I’ve written a number of times on digestive ailments, so I feel you might enjoy my other articles. Please just use my search box as it is too much to try to cut/paste everything in this small space. I have archived all my articles here, and there are some videos on youtube with suggestions. Marshmallow, slippery elm, probiotics, etc. Thank you.

  52. Julie October 26, 2015 at 11:44 am - Reply


    Please explain the difference between high histamine and high tryptase levels. Would you make the same recommendations to someone with high Tryptase?

  53. Deanna October 27, 2015 at 1:22 pm - Reply

    Suzy: Thank you so much for your informative article. After reading it, i am quite sure that HIT is an issue for me and two of my sisters. I will definitely ask my doc for lab work To identify snps.

    My doc put me on a Paleo diet over a year ago, and it just didn’t make me feel well. Now I see that the fermented foods, fermented beverages, bacon, vinegar, tomatoes and spinach were causing a worsening of some of my symptoms. After reading your article, I downloaded an app to journal my foods and symptoms and in a short time, i was able to identify foods that were exacerbating some of my symptoms.

    My question for you relates to candida. I have a recurring systemic candida infection that just won’t go away. I’ve been dealing with this for three decades now. Luckily, I have a great functional doc who is on it. She has me taking ketoconazole / nystatin (rotation) and some of my symptoms went wild. Yes, i am very sure this has to do with the die off, but i think HIT has a role in it, too. Would these drugs be considered drug muggers for DAO or HMT? Just curious.

    Thank you for your response!

    • Suzy Cohen November 2, 2015 at 4:25 pm - Reply

      It’s a great question, there are no direct studies on those drugs with those specific nutrient depletions so I cannot say for sure. If I were to guess, I’d say no. You may have an expressing gene snp though. I am not a believer in high glutamine which many doctors advise for healing the gut. If you have a good functional doc she will know what to do.

  54. Jessica October 27, 2015 at 4:06 pm - Reply

    So very interesting! I have lyme, mant coinfections, mold toxicity and have not been able to treat due to die off causing suicidal reactions. Anyways, one of hte first “symptoms” i had before I was diagnosed was a tingling of my lip and then it would swell up. Also swollen hands and feet. Then i did not experience this for 6-7 years and now in the last 4 months (after a reexposure to mold) I am experiencing the tingling lip and it swelling up. I don’t know if its a coinfection reaction or a histamine reaction. I suspect that I have histamine issue because of the inablity to handle fermented foods (causes anxiety and excitotoxicity). I also have many many snps. Does this sound plausible? Also any suggestoins on practioners who can handle ALL of these issues. I appreciate that you stay up to date on all this, thanks you!

    • Greg williams April 6, 2016 at 2:29 pm - Reply

      I get severe cold sores on my lips. So does my daughter and friend. Someone told us to take L-Lysine and a 500 unit daily prevents their occurance.

  55. Rivane October 28, 2015 at 3:08 am - Reply

    Hi Suzy, I havê RA, but i know im histamine intolerence, when i eat some food high histamine my joins swollen a lot, it is possible, please tell me some thing about that


  56. Jen October 29, 2015 at 2:51 pm - Reply


    I love your writing style. It’s a good balance of detail and easy to comprehend. I am wondering if it is a chicken egg thing with MTHFR and severe gut dysbiosis. I am at the point that I can hardly eat anything (yet keep gaining weight). I am wondering if Nystatin would be making my bloating even worse. I have used it for three weeks and have the worst joint pain, mood swings, bloat, and food cravings I have ever had and depression. My GI Dr says I have to take it but I am thinking it is not a great choice for me as I am hetero MTHFR and have UC. I am only eating minimal veg and meat and some olive oil currently. Do not drink, smoke etc. I am just not sure if I should be healing both at the same time. I am trying low sulfur and histamine currently but go off and eat rice or grain after weeks. 🙁

  57. Sue Medina October 30, 2015 at 12:23 am - Reply

    I tried taking probiotics a few times and each time, I feel very depressed. Can you explain why this happens ? Might it be related to histamine ?

  58. Shawnie November 1, 2015 at 4:25 pm - Reply

    Hello Suzy and Everyone!

    I am looking for a good Low-Histamine diet. Suzy, what would you suggest? And is anyone getting the help needed by eating this way?

    I’ve been looking on the net for lists and diets. What I have found is one diet is amazingly different from another, in the foods allowed to eat. Some of those foods, I can not tolerate, but I understand everyone’s allergies/intolerances can be different.

    But it still leaves me to wonder – a lot. lol – so this is the reason for this post.

    Thank you!


  59. Barb Dyjak November 3, 2015 at 10:12 pm - Reply

    In my 67 years, this is the single most helpful article I have ever read. Although I see an holistic MD, who has helped a lot, there are still issues. Now, I know why. Since I base my diet around eggs, mainly because I have been sensitive to casein and gluten for decades, and need to keep my carbs low, I find it necessary to rethink my whole diet. I confess, I am at a loss as to what to do. I had been relying a lot on goat products, because I thought only cow products bothered me. Now, it is amply evident that I cannot tolerate any level of casein, sheep cheeses included. I need protein, and like meat, but not three times a day. Any suggestions? I have begun to use quinoa. This is going to be interesting!
    I also know, sadly, that I am sensitive to chocolate, though it causes symptoms different from the gluten, etc. It causes sneezing & typical hay fever reactions. So, until now, I avoided it only during pollen season. Now, I know better. The proteins I have issues with cause pain: joint, muscle & nerve. Very debilitating.
    By the way, I don’t know if it relates to histamine, but, all the varied forms of MSG cause symptoms worse than any of the above: a real poison!
    My husband recently discovered through an IgG test, that he is sensitive to gluten, eggs & casein: How does this test compare to the histamine determination test? How do you test for dopamine levels?
    I cannot stress enough how enormously helpful this article is! Thank you, Suzy!

    • Suzy Cohen November 4, 2015 at 6:10 am - Reply

      Barb, the fact that you have such a bad reaction to MSG (monosodium GLUTAMATE) tells me something. Did you realize that whey proteins and protein shakes contain a lot of glutamate? Maye this is part of the problem. I was going to recommend PEA protein, but it too has glutamate, and you said it can “cause symptoms worse than any of the above; a real poison.” Maybe all your protein is giving you glutamate toxicity (or another way to say that is low GABA). Put that in my search box.
      Also, one more thing, protein is converted to homocysteine in the body, and it may get stuck there and homocysteine in high amounts is a cardio and neurotoxin. Your pathways may be cramping there. A doctor can help you with this. IgG is not the same as histamine.

  60. Susan F. November 5, 2015 at 12:31 pm - Reply

    My allergist told me those food panel tests for igG are a scam. He said igG to a food is protective. I had one those companies also tell me I was allergic to watermelon because it showed igE high but I had no such reaction at the allergist office. I really don’t know what to believe when it comes to those tests but real allergy MDs don’t believe in them. I have that bad hnmt snp and Mao and bad c677t . I bet it’s causing my arthritis somehow. One time I got totally dizzy one night. I couldn’t stand up all night. I blame a histamine reaction to some homemade wine with natural yeasts from my grapes. If you are interested in histamine or salicylate diets there’s the failsafediet. Thank you so much Suzy for shedding a light on a topic few doctors even consider!

  61. Maile November 5, 2015 at 4:12 pm - Reply

    I am wondering if bio-identical hormones have the same MIS effect as synthetic. Thank you!

  62. Michelle March 6, 2016 at 8:44 pm - Reply

    A very very helpful article and research! Thank you Suzy.
    I always knew that although I am relatively healthy something goes rather amiss when I drink even small amounts of wine or beer.
    I am also extremely intolerant to ALA supplements as well as Glutathione and anything that has sulphur or methionine! my eyes droop if I consume even tiny amounts of the above or Taurune. I have a great muscle tone and bone density, yet feel incredibly tired almost all the time and sleep takes over my days.
    This is incredibly frustrating as I barely get anything done! I am at my wits end as i ve tried and researched all I could but still have no answers. This great article is yet another beam of light in the dark tunnel, but I have yet to find my answers..
    Another avenue I persued was mitochondrial poisoning with Mercury through amalgams and bad replacements without protection. I tried detoxing with chlorella and dmsa with
    disastrous results, so gave up.

    Is it possible to be able to retain and build muscle yet have disfunctional mitochondria..? I feel I am living my life through a constant daze and brain fog. The fatigue is crippling and demoralising! I am also hetero for 1298c mthfr
    Please give me some more clues.. I feel I ve tried and exhausted everything with no solution in sight. :(( sos

  63. Catherine March 11, 2016 at 7:23 pm - Reply

    Suzy, my iPad is littered with icons describing Histamine intolerance and all the confusion surrounding this syndrome in terms of what you can and cannot eat.

    This article has hooked me to you into reading anything and all things relating to the gut.

    Do you give co suits?

    • Suzy Cohen March 12, 2016 at 7:50 am - Reply

      Hi Catherine,
      Histmaine is such an interesting molecule, and there are at least 2 kinds, H1 and H2.
      And then there’s the leukotrienes.
      No I don’t consult any more, there’s one of me and thousands of readers each day, but thank you for asking. I’ve archived hundreds of articles here at my site, and there is a little bit more on histamine and its relationship to headaches/clusters and migraines in my book, Headache Free.
      The gut the gut, it’s one of the best places to start but it’s not the only consideration.

  64. […] Allergies and Your Genes – Histamine, Autoimmunity and DAO SNPs […]

  65. Eileen Orsett March 31, 2016 at 8:25 pm - Reply

    Thanks for all that information. I am so depressed about having these reactions to things I never was allergic to. 4 visits to the ER near Anaphylaxis, couldn’t talk or move arms or legs. I did not eat anything but my mixed nut breakfast with coconut milk and blueberries. I still eat the milk and blueberries. It feels better knowing what I know now.

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