Parasite Infections: The Mast Cell Activation connection

parasite infections and mast cell activation histamine intolerance

If you’ve been following these articles for some time you’ll know that I write about Blastocystis infections quite frequently

It isn’t a coincidence. I contracted this unpleasant bug a few years back and have tried a range of treatments from straight up antibiotics to multiple herbal antimicrobials protocols.

For some reason, and I know I’m not alone, certain Blastocystis infections are very recalcitrant and difficult to treat (4).  Let’s not leave out the Dientamoeba infection either. For me these two bugs have been impossible to clear.

I must say that the herbal antimicrobial protocols helped considerably. Containing a whole range of herbs including

After the herbal protocols I felt immensely better. So much so that I assumed I was clear and free of the parasite infections. Lo and behold, minor gut symptoms returned, mainly bloating after food. This is a good place to mention the essential importance of retesting after a treatment. If I had never retested I would still think that the bizarre and seemingly unrelated symptoms have nothing to do with Blastocystis hominis infection.

Update – After years of trying different herbal antimicrobial approaches I have managed to clear the two parasite infections and have learned a ton about the different herbs that work, which ones may negatively impact your beneficial gut flora and have formed some ideas on how long to take herbal medicine to get the best results.

Mast Cells

This brings me to the subject of this article. Mast cell activation in the presence of a gastrointestinal infection. When I first heard about mast cells and histamine intolerance my eyes glazed over and I lost interest in the white paper I was reading. Fast forward a year and I have certain unexplainable symptoms such as

  • Chronic sore throat
  • Sore lymph nodes just under my ears
  • Headaches
  • Fatigue and exhaustion
  • Bizzare food intolerances (more on that later)
  • Chronic sinusitis

Seeing as I didn’t have any gut symptoms I didn’t relate the upper respiratory tract issues with my gut infections. Then I heard a story from a practitioner friend who was treating a patient with the exact same symptoms plus a Blastocystis and Dientamoeba infection. So I decided to hit the literature and see what connections there might be.

Mast Cell Function

First off it is important to note that mast cells aren’t the problem here. One paper notes the beneficial immune functions these cells play in the human body that help maintain homeostasis including

  • Tissue repair
  • Angiogenesis
  • Innate immune function
  • Adaptive Immune function
  • Immune tolerance
  • Mediators of inflammation

“The strategic positioning of MCs at the interface between the host and the external environment near blood, lymphatic vessels, nerve fibers and a range of immune cells, including epithelial and dendritic cells, allows them to act as sentinels of invading microbes and respond rapidly to any change in environment by communicating with different immune cells” (7).

They have been described as sentinels, ready to deal with whatever comes their way. Definitely helpful allies but problematic when we keep triggering them into action.

mast cell activation parasite infection blastocystis dientamoeba byron bay gut health gut infection parasite

Image taken from Mast CellsPhenotypic Features, Biological Functions and Role in Immunity

In the picture above we can see that upon activation mast cells degranulate. This process involves the release of a whole range of different molecules including

  • Histamine – possibly the most important in our discussion
  • Cytokines – these are messenger molecules that can be pro-inflammatory or anti-inflammatory depending on their specific makeup
  • TNF – an inflammatory cytokine
  • Interleukins – 4,6 and 15 – yet another set of cytokine messenger molecules

Mast Cell Activation

How are these cells activated?

In the Fundamentals of Inflammation Joshua Boyce describes mast cells as a front line defence mechanism. As mast cells reside close to external environments such as the skin the airways and the gastrointestinal tract they are perfectly positioned to deal with incoming problems and degranulate, or release the contents listed above, in a range of different scenarios

  • IgE based allergies – proper allergic reactions that involve type 1 hypersensitivity. The most severe type 1 hypersensitivity is anaphylaxis
  • Pathogens
  • States of inflammation – an example here would be mucosal injury

While the first example of IgE based activation of mast cells is well understood and known for quite some time, the last two examples are worth more attention. Mast cell activation occurs from parasite infections (Blastocystis, Dientamoeba) and bacterial dysbiosis (Helicobacter, Klebsiella) as well as injured intestinal mucosa which is a consequence of such infections.

The resulting symptoms can be wide ranging and seemingly unconnected to a gut infection.

My symptoms included upper respiratory tract inflammation, headaches and extreme food sensitivities to histamine rich foods. Other symptoms of mast cell activation can include chronic/recurrent 

  • Flushing
  • Pruritus
  • Urticaria
  • Angioedema
  • nasal congestion 
  • Wheezing
  • throat swelling
  • Headache
  • Hypotension
  • Diarrhea

The list of symptoms comes from a review entitled Mast Cell Activation Disease and Microbiotic Interactions. The authors included an important point that all other disorders that could account for these symptoms need to be ruled out.

Take Home Points

Coming back to my personal experience I noted after a year or so of chronic Blastocystis and Dientamoeba infection there was a shift in symptoms from gut related (bloating, stomach ache, loose stools) to upper respiratory tract (chronic sinusitis aka blocked sinuses, sore throat, sore lymph nodes) all triggered from different foods. Cutting back on high histamine foods (coffee was particularly hard) has helped relieve the symptoms considerably but they aren’t gone by any means.

The link between mast cell activation and parasite infections is starting to be explored in the scientific literature (12,13,14,15,16). Understanding that many extra-intestinal symptoms may lead back to a gut infection is a key learning.

Proper gut testing is essential.

Are you suffering from symptoms that may be from mast cell activation? Leave a comment below.  

References and Resources

  1. Blastocystis hominis – A Protozoan Gut Parasite
  2. Blastocystis homminis – Probiotic Treatment
  3. Blastocystis hominis – Skin Disorders and Gut Infections
  4. Treatment failure in patients with chronic Blastocystis infection
  5. Stool Testing – My Personal GI Results CDSA + PCR
  6. Mast Cells and Anaphylaxis
  7. Mast CellsPhenotypic Features, Biological Functions and Role in Immunity
  8. Fundamentals of Inflammation
  9. Helicobacter Pylori – A Notoriously Popular Bacteria
  10. Klebsiella – Bacterial Dysbiosis, Detection and Treatment
  11. Mast Cell Activation Disease and Microbiotic Interactions
  12. IgE and mast cells in host defense against parasites and venoms
  13. Mast cells in allergy and infection: Versatile effector and regulatory cells in innate and acquired immunity
  14. Mast Cells in Gastrointestinal Disease
  15. The Role of Mast Cells in the Defence against Pathogens
  16. The Roles of Mast Cells in Parasitic Protozoan infections
  17. Recommended GI testing – CDSA + PCR
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  1. After losing a lot of weight almost 2 years ago after a heap of testing nothing was noted. But accompanying the weight loss was rashes around the eyes headache, fatigue and the feeling of tightness in neck. As well as irregular heart beat and all the other lovely stuff.

    After being plagued on and off and not feeling right for almost a year and a half slowly gained some weight back then was hit again with the same problems more testing to eventually confirm Dientamoeba.

    Haven’t explored antibiotics yet, doctor seems reluctant but life is miserable like this, and now depending on what I eat the symptoms of histamine intolerance get worse.

  2. Hi I’ve had blasto for 6 years and haven’t been able to test it with antibiotics successfully. I don’t eat gluten, dairy or sugar. But I do eat carbs, otherwise I’d be too weak. I’ve been diagnosed with MCA and POTS. However I beleive my gut infection is the root of all this. What was your protocol and how long did it take you. I feel I really need to get rid of this to be well again. Any advice would be a big help.

      1. I have Mast Cell. Sore throat swelling neck respitory problems. Intolerance to foods. POTS EDS and other problems. No one here treats Mast Cell your on your own. I have inflammation in my gut. And my lymph nodes in my neck get swollen. Like I have inflammation all through my body. I’m miserable

  3. Hello Todd,

    Thanks for sharing this article.I am happy that you resolved your issue. I was also tested positive with blastocytis and immensely sensitive to histamine containing and releasing foods.

    Would you elaborate your herbal antibiotic approach a little ?
    which of the herbal choices contributed most to your healing ?

    1. hey kaan, I have covered some of the herbs that helped shift my gut health back into balance here

      I’m not 100% positive that blastocystis is the issue in most people that have it. I think because it is easy to find on a cheap stool test that we blame it for other, harder to find, gut conditions. Things like SIBO, food intolerances and allergies and even large bowel dysbiosis should be on your radar, especially if you are struggling with histamine reactivity. The good thing is that all of the herbs that we use to treat blastocystis can help resolve bacterial overgrowth problems too.

    2. Every thing sound like the problems I’ve had for years. Taking years even to realize parisite’s was a issue. Treatment for them is never ending and I wonder how I’m even alive. Now the skin, the itch the crawl. The over growth in cells, callucus, thickening, cracking, sores and scares. Light, smell, a touch can drive you mad. Dizzy, disoriented, weak pain, electrical buzz, shooting pain, rolling pain, eyes, ears ,throat, joints burn, knots and tumor like bumps like rocks on ankles knees hips shoulders. Jaw and face pain. I could go on and on.

    3. Have you tested for Lyme disease? It is a common root cause of MCAS and over time depletes the innate immune system thus leaving the possibility of reactivation of old infections or conversion of certain bugs to a more pathogenic state. Intestinal parasite plague people with Lyme more than others. It is important to get tested by a LLMD. Good luck

    4. I’ve been struggling with Gut issues for almost 2 years. In the beginning I was diagnosed with calitis, then diverticulitis I was on 4 or 5 antibiotics which finally Cipro helped the most and I was able to get back to work. I was cleared up for 2 months. I have been eating a lot of garlic and I am taking Levitox. It seems to be helping a little. I am going to my doctor in the 8th of April. I investigated parisites for 18 months and on my own I started taking Levitox. Does anyone have advice on questions I should be asking a doctor

  4. I have been dealing with fatigue, heart palpitations, Anxiety, new extreme food sensitivities, asthma like symptoms, and there’s probably more, for the last five+ years. I have tried to treat for Lyme disease in the past with an iffy test, but couldn’t tolerate treatments. I was diagnosed through a stool test with klebsiella pneumonia, and treated that with biosidin and grapefruit seed extract. I felt better for a while. I also had a cavitation surgery on my old wisdom teeth sites, and they tested and said I had some sort of entomoeba parasite there. I’m wondering if all my symptoms could be from these parasites and disbiotic bacteria? What tests do you recommend to see if these things you mentioned are an issue for me? I live in the USA. And what type of dr could help me with this? A GI doctor?

    1. I forgot to mention that I am currently being treated for mast cell activation syndrome with antihistamines and mast cell stabilizers. It is helping, but I know not the cure. I’m trying to figure out what is triggering my mast cells.

      1. Hey Becky.

        It sounds like there may be a number of things contributing to your mast cell activation symptoms. The best approach, especially for chronic conditions, is to get to the bottom of what is triggering this response (often not as easy as it sounds). Lyme testing isn’t the greatest at the moment, and the entamoeba parasite results probably need attention too! Dysbiosis is best assessed with a microbiome stool test. I have been recommending Thryve to my patients now that Ubiome is out of business.

  5. Hi Todd,
    My symptoms seem to be related to many things – I was treated for acute Lyme over 20 years ago. In 2014 after a few years of searching for reasons for nerve irritation, numbing, pain, brain fog, and a host of other issues including bloating, constipation, endometriosis, fibroids…and the list goes on, I regretfully began antibiotic treatment for chronic Lyme/ Bartonella and other co-infections. I have been on an antibiotic rollercoaster for over 6 years and my body is a wreck. Symptoms can be related to a messed up gut, mast cell (swollen nasal passages, throat, white tongue (not yeast), nerve irritation. Not sure if you treat patients in the U.S., if not, any connections in the New York area?

    1. Hi Karalyn, thanks for sharing your experience. Unfortunately no I can’t take on patients in the USA and I don’t have a great referral either. So sorry I couldn’t be more help!

      1. Hi I same I cfs
        But love to some your herbs
        I recently got diagnosed with
        Blastocystis but I had for 5 years or more
        So these little shits are to rid of
        So I wonder how much costs?

    2. Hi Karalyn, If you are in New York try to head to Boston. They have the only Mast Cell Clinic in the USA. They can answer a lot of questions you have. Also, be very cautious about those antibiotics!! They can do more harm than good. Plus, there are other ways you can treat lyme. Have you tried to completely change your diet to antihistamine? Your body is definitely “chemically” (modulators) over stimulated. That change could make a significant difference in your symptoms. Good luck!! I hope you get answers and start feeling better soon.

  6. Hi I same I cfs
    But love to some your herbs
    I recently got diagnosed with
    Blastocystis but I had for 5 years or more
    So these little shits are to rid of
    So I wonder how much costs?

  7. This is a really interesting article, thankyou.
    I have been suffering with face flushing,angiodema, racing heart, tinnitus and oral food allergies for 18 months. An immunologist said it is Salicylate sensitivity but a low Sal diet hasn’t fixed it. A local naturopath said to get tested for Blasto and it as well as dientamoeba is positive. I have an appointment with her this week. Yours is the first internet article I have managed to find about this. Thanks once again.

    1. I’d been struggling for years thinking I had salicylate sensitivity, just tested positive for blasto after I concluded I must have a histamine intolerance from MCAS. I’m not sure if I have it all, or if my diet may resume back to normal after an antibiotic. Frustrating food intolerances hopefully discontinue after this round of antibiotic.

  8. Wow…thamks for the article, O 4elate so much…I have mast cell activation syndroms and believe its a fut issue too, based on research heavy met asl toxicity asnd ch e mic a l toxicity too. Would you recommend coffee enemas as part of your herb healing protocol, Ive read much about them, but havent tried yet. Curious if this was also s part of your healing.

  9. My daughter (age 15) has been dealing with anaphylaxis and other similar symptoms that suddenly began 1yr ago (post COVID infection). She’s been seen by at least 5 pediatric specialists & diagnosed w/ Systemic Mastocytosis but no medication has helped her condition. After a ton of research on my own I have suspected parasites. With all of the information I have gathered, I’m not sure why all of her doctors have not ever suspected or tried to test for parasitic infection. I am currently waiting on a black walnut, wormwood and clove tincture to come in the mail and just came across your article on this subject. Its been a very difficult year for my daughter and I am hoping that herbal medicine will heal her body. She’s suffered with GERD since birth, gut issues in general but why do so many medical professionals overlook the possibility of parasites causing so many gut issues.

    1. Hi Beth, thanks for taking the time to share your experience. I would push for some functional testing to get to the bottom of your daughters chronic illness. I have found the OAT test to be a great place to start. Parasites could be an issue (a good quality stool test should find them if they are there) but also mould exposure can trigger many histamine mediated conditions too.

    2. Hello Beth,

      I am also experiencing sudden anaphylaxis post-COVID. Skin prick test did not reveal allergies. The only thing that has helped is a very restrive, low-histamine diet. Has your daughter’s condition improved since?

      1. I should also mention that I did a stool test, which did not find any parasites. However, they did find extremely high levels of the bacteria morganella. This bacteria is linked to histamine production. Grapefruit seed extract was one recommendation but I have yet to try it due to fear of reaction.

    3. Hi Beth, I’m sorry about your struggles. My child was diagnosed with a mast cell disease as well. The misunderstanding and lack of info about the disease is awful. Does your daughter have any lesions (called mastomas) anywhere on her skin? Many systemic will have one active mastoma somewhere on their being. They can be internal too. In stomach lining or organs. Did they check her DNA? She will have a mutation on her KIT gene if she does, infact, have systemic. Many doctors will take forever to do the test because they assume childhood kind is not systemic. Usually cutaneous or activation syndrome. Have you ever tried Cromolyn Oxide powder or oral? Does she take a antihistamine daily? Change her diet completely to antihistamine. And try to provide a fresh apple at every meal. Apples are natural Mast Cell stabilizers and can give her A LOT of digestive help. Again, so sorry you are dealing with all that. I hope my added info can help you!! Good luck with everything!!

    4. I know this is an old post…but I’m also waiting on the same parasite cleanse that I just ordered today (clove, black walnut, wormwood), and I’m wondering if I will be able to tolerate the green black walnut since walnuts are high in histamine. It may be fine considering it’s just the hull, but did your daughter tolerate it well?

  10. Thank you very much for the articles. They are very informative! I wanted to ask how long it took before you saw improvements in your food intolerances following treatment? Is this something that happens at the same time or do the intolerances take a while to go away after your gut is back to normal? Thank you.

    1. Pleasure! It varies from patient to patient depending on what is driving the intolerances. Sometimes it is leaky gut other times it is a co-factor deficiency (think nutrient/vitamins/minerals) leading to enzyme dysfunction. Treating the overgrowth or infection then healing and sealing the gut is the general approach. Nutrient repletion can be a total game changer for food intolerances.

      Hope that helps!

  11. Dear Todd Mansfield,
    Thank you for the great article! I was looking on internet because I have high tryptase and the oncologist (who excluded cancer through a marrow biopsy) told me that could be Mast Cell Activation Syndrome. I have back pain due to three fractured vertebraes and my muscle around are still sore after 6 months. I am 42 and they diagnosed me with osteoporosis. They do not know what caused me losing so much calcium after breast feeding my baby. Do you know if there is any link with mast cell and back pain? I am not sure if they are related or there are two separate things.
    Thank you very much!

    1. Hi Roberta! Mast cells can cause pain in any part of the body due to inflammatory (and many other) issues they can cause. Mast Cells can even cause inflammation in the brain. Mast Cell Activation Disorder can give you many unexplained issues. My child has a mast cell disease. I would think you would have other symptoms, as well, if you have a mast cell issue. Maybe ones you might be overlooking?? Do you have any stomach or digestive issues? Unexplained skin issues? Any brain fog or memory loss? Any continued cold symptoms? You could have something different altogether like a degenerative disk disease, or a connective tissue disorder, which can prevent you from healing and cause you to use up your stores of vitamins. Or it could be as simple as your gut and diet. I know many people with similar symptoms as yourself. Along with knowing some about Mast Cell issues. Mast Cell, inflammation and diseases do go hand in hand. But, I will say, if it is just your spine, then I, personally, would not think Osteoporosis. If it was that, then there would be signs in other places besides your spine. Have you broken any other bones? How often? Have you had a bone density test done? Have you always taken a long time to heal? Are you flexible? There are DNA tests(and other tests) that can be done to pinpoint if you have certain things I mentioned up above. But please, always follow your instincts. If you feel like your diagnosis is wrong or off in some way, look elsewhere. Get second and 3rd opinions because your instincts are usually correct. Good luck with everything!! I truly hope you find clarity in your journey! Along with peace of mind and proper treatment!!

  12. Hi there! Your post has been absolutely amazing to read! My son has Mastocytosis (a mast cell disease). They say cutaneous, due to him having it in childhood, but I believe it may be systemic. To explain the issues He has, and the how, has been so hard. Even to do so to professors that teach about these very things at top places like Dartmouth and Harvard. I printed off your post, and showed it to his school and doctors. It has really been helpful in getting them to understand and to be on the same page. So, thank you for your journey and post. Even thought it sounds like it was a trying experience to go through.

  13. Hi,
    I have been suffering the same symptoms like indigestion, bloated, gas, abdominal pain, loose stool, acidity, soar throat, itchy skinny, fatigue, breathing problem and many more…
    Many time diagnoses with parasitic infection in my stomach, not get any help yet. Please help if you can know my issue

  14. Great article! I found it through a search ‘kleibesella mast cell activation’. To the point – I have a host of neurological symptoms (dysphonia, balance, cognitive, mass fatigue, mild ataxia, stiff neck..) that occur approximately 6 hours after eating starch. It is progressive – used to tolerate about 30 gram per day; can now only tolerate 8grams per day. I have no stomach issues, except that a scope recently revealed mast cells and polyps (some bleeding). I currently stay on a keto diet. The only drugs so far that have an affect are prednisone and Valproic acid when I test by introducing a starch food at about 35 grams (example: potato). My doctors are now considering Mast Cell Activation and I have read too about ankylosing spondylitis (I have spinal degradation as well). Any ideas on what to test next? My neurologist suggests berberine; allergist suggests Omalizumab. Can you suggest anything else?? I have been suffering now for over 10 years and now have complications to the keto diet. Anyone here have anything similar??

  15. Hi. I’m so pleased to have found this site and article even tho it’s a little bit old now.

    I’ve not felt well since a bout of food poisoning about 12 years ago. I’ve had gastro issues, mainly diarrhoea on and off (diagnosed as IBS), joint pains, gallbladder inflammation etc etc. About 2 years ago I also started with skin problems which have become really bad and uncontrollably itchy with flushing and palpitations.

    I recently had a comprehensive gut test and and discovered dysbiosis, low SCFAs, low IgA and Blastocystis. The doctor gave me Metronidale. I’ve also just had a Total IgE test which showed a level of 1660 (normal is 0-81) !!

    Maybe my experience will help someone, altho I’m not sure of the next steps now. I’ll carry on reading.
    I’m in the UK – the doctor had never heard of Blastocystis!

    Keep on with the good work

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