Those who follow me on Twitter will have seen me talk a lot about histamine over the past month and a bit. It has become a central focus of my independent research and I have been running experiments on myself in order to see if I have a histamine intolerance.
This will be a 3 part series – the first I will cover is how I ended up looking into this, the second will explain the role of histamine in the body, and the third will look into the effects of a low-histamine diet on my health.
I want to give a bit of back story for how I started to get interested in this particular avenue.
SSRIs never worked for me, and I ended up with microscopic colitis from Sertraline
TW / Gross stuff / Medical stuff
Late last year I discovered after a biopsy done during a colonoscopy that I appear to have microscopic colitis, rather than having a Crohn’s disease resurgence. This made me begin to question a lot of things about my past, in fact before my colonoscopy I had been going through my health notes as a detective.
I was started on Sertraline in the mid 2010s. I then complained about diarrhea and nausea symptoms, but this was attributed to my Crohn’s disease having another flare, but the location of this flare was not the same place as when I had previously had it, and it wasn’t near my resection site.
For the next five years I was in and out of hospital with increasing doses of Sertraline to manage the depression that it appears that was mainly a result of Sertraline – it caused multiple issues in two different work places – I spent roughly nine months with painful anal fissures waiting for operations to fix them.
During this time I actually stopped taking Sertraline and tapered off it with my doctor’s knowledge. That year I didn’t have any anal fissure complications, however when a series of external to me life events happened (my father dying, one of our cats passing, and a family member having a breakdown), it was agreed that I should go back on it to make it through this period.
Shortly afterwards, gastro complications occurred again. I complained about nausea and diarrhea and was told to persist. Then sure enough, I needed another operation. It has now been confirmed that this can be a complication of Sertraline in some people.
How does this work though? It’s a “brain” drug.
This made me begin to wonder the mechanism of action that could actually cause this in me. It turns out that there are different serotonin receptors in the body, and in fact 95% of all serotonin is stored in the gut, not the brain.
A few of these receptors are largely responsibility for gut motility (or the passage of food through the bowel). Sertraline works as an 5HT3 Agonist (one of the different serotonin receptors) – meaning that it drives the uptake of serotonin through this receptor. Unfortunately this was causing food to rush through me and causing me to process a lot of undigested food in my large colon, this caused damage to the walls of my intestines, and as a result I ended up with anal fissures and microscopic colitis.
Long COVID / MCAS / Histamine Intolerance
Roughly around the same time I was looking into science into Long COVID with the rise of the Omicron variant, and the possibility that I would likely end up with it if I contracted the virus I began investigating possible things that would help to prevent this from happening. It was here I discovered histamine intolerance, Mast Cell Activation Syndrome, and their relation to Long COVID.
Histamine’s role in the body is still largely under researched
When I saw this diagram on this MCAS website, I was floored. These are the complications I have been dealing with my entire life at different times and in different ways. I will highlight the ones that are relevant to me below.
In a more expansive list they have these ones – in italics are the ones I have:
Eyes – Red eyes, irritated eyes, dry eyes, burning eyes, difficulty focusing vision, and conjunctivitis (pink eye).
Nose – Nasal stuffiness, sinusitis, postnasal drip, hoarseness, laryngitis, nose bleeds (epistaxis), and intranasal sores.
Ears – Ringing in ears (tinnitus) and Eustachian tube dysfunction (blocked, popping ears).
Throat – Vocal cord dysfunction, throat swelling, sores on tongue/mouth, itchy throat, burning mouth, and difficulty swallowing
Skin – Hives, angioedema (swelling of the skin), skin flushing, itching, skin rashes, dermatographism (when scratched skin causes a red welt), chronic itching, urticarial pigmentosa (legion/hive-like spots on the skin), flushing, bruising easily, reddish or pale complexion, cherry angiomata (skin growths), patchy red rashes, red face in the morning, cuts that won’t heal, fungal skin infections, and lichen planus.
Cardiovascular – Fainting, fainting upon standing, increased pulse rate (tachycardia), palpitations, spikes and drops in blood pressure, high pulse or temperature, high triglycerides, lightheadedness, dizzy, hot flashes, and postural orthostatic hypotension syndrome (POTS).
Respiratory – Wheezing, asthma, shortness of breath, difficulty breathing deep, air hunger, dry cough, chronic obstructive pulmonary disease (COPD), and chronic interstitial fibrosis.
GI Tract – Left upper abdominal pain, splenomegaly (enlarged spleen) epigastric tenderness, nausea, vomiting, diarrhea and/or constipation, abdominal cramping, bloating, non-cardiac chest pain, malabsorption, GERD/acid reflux, cyclic vomiting syndrome, colonic polyps, and gastric polyps.
Liver – High bilirubin, elevated liver enzymes, and high cholesterol.
Neurological – Numbness and tingling (especially in the hands and feet), headaches, migraines tics, tremors, pseudo-seizures, true seizures, waxing and waning brain fog, memory loss, poor concentration, difficulty finding words, and spells of cataplexy (suddenly becoming disconnected from and unresponsive or unreactive to the world around).
Musculoskeletal – Muscle pain, fibromyalgia, increased osteopenia, osteoporosis, weakness, and migratory arthritis (joint pain).
Coagulation – History of clots, deep vein thrombosis, increased bruising, heavy menstrual bleeding, bleeding nose, and cuts that won’t stop bleeding.
Blood disorders – Anemia, increased white blood cell count, platelets, decreased white blood cell counts, decreased neutrophils, decreased lymphocytes, decreased platelets, reductions in CD4 helper lymphocytes, reductions in CD8 positive suppressor lymphocytes, reductions or excesses of IgA, IgG, IgM, IgE, a known condition called MGUS, myelodysplastic syndrome (reduced red cells, white cells, platelets), and increased MCV (mean corpuscular volume).
Psychiatry – Anxiety, panic, depression, obsessive compulsive disorder (OCD), decreased attention span, attention deficit/hyperactivity disorder (ADHD), forgetfulness, and insomnia.
Genitourinary – Interstitial cystitis, recurrent bladder infections, sterile bladder infections, and frequent urination.
Hormones – Decreased libido, painful periods, heavy periods, infertility, and decreased sperm counts.
Dental – Deteriorating teeth.
Anaphylaxis – Difficulty breathing, itchy hives, flushing or pale skin, feeling warm after exposure, weak and rapid pulse, nausea, vomiting, diarrhea, dizziness and fainting.
How do I test for it?
Well, this part is harder, I cannot definitively say that I have MCAS with a histamine intolerance, but there were a number of indicators. Last year I started to investigate my genetic data – I had signed up for Ancestry to confirm a family tree I have (surprisingly it’s incredibly accurate). This gave me access to my DNA data. I started to use health websites to investigate what was going on with my health.
Genetically, I shouldn’t have ADHD according to what we know about ADHD genes
Using a site called Self-Decode (which was one of the more expensive sites) I came out with this result:
I definitely have ADHD, but the origins of mine might come from somewhere else – namely I think I have it due to things related to histamine.
There are some key genetic mutations associated with MCAS though – one of them is the MTHFR C677T Gene.
MTHFR – C677T Mutation
This is taken from Genetic Life Hacks (a much cheaper health analysis tool, but with less content than others).
I have extremely reduced enzyme function for methylation – this can lead to among other things – histamine intolerance.
On top of that I have a few HMNT and DAO enzyme genetic mutations, these are the enzymes used for breaking down histamine in the body. I unfortunately have less of an ability to do this as well as having a shorter bowel which means that a lot of histamine isn’t eliminated from the body due to less ability to process it.
I am a perfect candidate for histamine intolerance.
But histamine is just a thing that is related to having itchiness I thought?
In part two I will explain just how expansive the role of histamine is in the body – and how I linked it to serotonin – in my case it might be directly responsible for the parts of ADHD that suck I have to deal with.
I will also explain the changes in my body and my mind following a low-histamine diet for 30 days – the results were nothing short of miraculous.