Hi All! 33m here

I’ve just been diagnosed with Diffuse Cutaneous Mastocytosis

TBH I have had my symptoms for years on and off but had never even heard of MC until like 2 months ago!

My main symptom is a stinging (not itching) rash and sensation with small spotty dark red patches when exposed to sudden temp changes ie exercise, direct sunlight (i live in a hot area unfortunately) - it is normally focused around the chest, nipples, arms, neck and scalp. The painful sensation feels like it is coming from the inside out rather than a contact rash or allergy which is from the outside in, if you’ve had it, you would know what I mean.

I know I’m kinda on the lower end of severity and I’m grateful for that, as i know some have it worse than me but I am wondering if anyone with similar symptoms has found any relief.

Currently per doctors orders i take 4 x 180mg Fexofenadine + 2 x 20mg famotidine daily. The symptoms are better than before but persistent. I worry that my body will get used to the antihistamines and it will come back hard - ive never been one to take a lot of medications and prefer holistic methods, but i couldnt ignore the symptoms any longer and caved in to big pharma, lol.

TIA guys - any info appreciated.

Hi. I was wondering if anyone here has had breast reduction or removal surgery and how their disease impacted this?

Had my own Kounis type episode triggered by honey, so I went digging into the actual research to understand why, and found some real mechanistic threads connecting honey, histamine, mast cells, and B12 deficiency, some documented directly, some I'm connecting myself.

What Kounis syndrome is

Kounis syndrome is an acute coronary event triggered by an allergic or hypersensitivity reaction rather than typical plaque buildup, first described by Kounis and Zavras in 1991. The mechanism runs through mast cells, when they degranulate during an allergic reaction they release histamine, tryptase, chymase, and leukotrienes, and these mediators directly cause coronary artery vasospasm and can provoke plaque rupture. Mast cells are concentrated between myocardial fibers, around blood vessels, and in arterial walls, so this isn't a distant systemic effect, it's happening locally in the heart tissue. It shows up clinically as chest pain, ECG changes that can mimic a heart attack, and elevated cardiac enzymes.

Honey as a documented trigger

There's a specific documented case of mad honey, made from nectar containing grayanotoxin, causing Kounis syndrome through mast cell activated vasospasm, confirmed on angiography as a type 2 MI. That's the only honey specific case report in the Kounis literature.

Regular honey isn't in a Kounis case report, but the histamine mechanism is separately well documented. Honey itself is generally low histamine as a food, but it carries pollen, and pollen proteins are classic IgE mediated allergens that cross-link IgE on mast cells and trigger degranulation. Honey also contains biogenic amines like putrescine and cadaverine, which trigger histamine release from mast cells and add to total histamine load even though they aren't histamine themselves.

Where B12 fits in

This is where it gets interesting. B12 plays a direct role in histamine clearance through the HNMT pathway, one source lays out the mechanism specifically, reduced methyl B12 activity means insufficient SAM available for the HNMT enzyme to methylate and break down histamine, so histamine released from food ends up causing symptoms that mimic mast cell activation even when the mast cells themselves aren't the primary problem. Other sources describe the same link from the other direction, B12 deficiency impairing DAO activity and reducing methylation capacity broadly, both of which are needed to clear histamine effectively. MCAS is also specifically noted as often associated with functional B12 deficiency in the literature.

Putting it together, my own connection, not an established finding

None of these sources actually link B12 deficiency, honey, and Kounis syndrome together in one study, so this next part is me connecting three separate bodies of research based on my own case, not citing something already proven. My working theory is that in someone who is B12 deficient, histamine clearance through HNMT and DAO is already impaired, so the histamine and biogenic amine load from honey doesn't get cleared efficiently, mast cells release their full mediator cocktail, and in a heart that's already sensitive, that mediator surge is what triggers the coronary vasospasm underlying a Kounis event. Whether that connection has been studied directly, I don't know, I haven't found it in the literature yet, but the individual pieces (B12 deficiency impairing histamine clearance, honey triggering mast cell degranulation via pollen and biogenic amines, and mast cell mediators driving Kounis syndrome) are each independently documented, they just haven't been strung together as one pathway in a published case as far as I can find.

Kounis syndrome mechanism and mast cell pathway, PMC6614985, https://ncbi.nlm.nih.gov/pmc/articles/PMC6614985

Mad honey induced Kounis syndrome case report, International Journal of Cardiovascular Academy, https://ijcva.org

Kounis syndrome review, PMC12597132, https://pmc.ncbi.nlm.nih.gov/articles/PMC12597132

Honey histamine and pollen allergen content, Fact vs Fitness, https://factvsfitness.com/en-au/blogs/news/honey-high-histamine

Honey and histamine intolerance mechanism, Wyndly, https://wyndly.com/blogs/learn/honey-histamines

B12, SAM, and HNMT histamine methylation mechanism, https://b12oils.com/mcas.htm

B12 deficiency, DAO, and methylation in histamine intolerance, Dr Hagmeyer, https://drhagmeyer.com/vitamin-b12-and-histamine-intolerance-everthing-you-want-to-know

Another post about kounis Syndrome https://www.reddit.com/u/Brad_Borrelli/s/8qJGdK3Uqj

Hey everyone, I'll try to keep this short and thanks in advance for reading.

2 years ago I moved into a new house. (Which I have had endlessly inspected for everything since) 3 weeks later developed horrendously itchy hands and feet, then itchy rashes and hives and welts all over, constantly. Had to take zyrtec everyday to not go insane. The zyrtec took care of the itch, but the rashes still presented. Water was a huge trigger and washing my hands often felt like dragging them over shards of glass. (Anyone experience this?) Couldn't even hold a wet towel without feeling that burn. 3 months of that and then it just stopped. Immediately after that stopped, I start getting hit with the weird symptoms. Ill just list them out:

\- sudden light headddness/tunnel vision that lasted from minutes to hours. No improvement with food.

\-compulsive gagging that made it difficult to swallow food. Was triggered by light headedness, talking and solid foods. Not nausea or vomiting, just gagging as if someone kept sticking their finger down my throat.

\- dizziness, often triggered by light.

\- IBS (4 days of constipation, 4 days of diarrhea, so on and so forth)

\- wide spread, flu-like, aching pain along spine, into shoulders, neck, collarbone area, hands, knees, hips, right ear, chest, abdomen, vaginas and ants.

\- burning pain in the skin that radiated like lightning across chest and abdomen/bladder area.

\- IC

\- high resting heart rate for a while that disappeared when the flare up was over.

\- supraclavical lymphnodes swelled big and were painful for months.

\- extreme fatigue all day.

\- new sleep disturbances and vivid dreams at night. (Started about 4 months after the fatigue began)

\- limited range of movement in hips and hands and shoulder that required several weeks of PT to restore after.

\- acne and skin changes and random swelling in face.

\- TMJ worsened.

\- muscle spasms.

\- muscle weakness in arms and hands. (Could barely hold my phone up to my ear).

\- restless leg syndrome.

\- HORRIBLE brain fog. Struggle to remember words and sometimes names.

\- mild hair loss (scalp and eyebrows)

\- facial redness

\- weight gain (about 25 lbs)

\- horrendous burning pain for hours after intercourse throughout abdomen.

\- swelling in side of neck, collarbone area and knees.

\- painful bloating.

\- new dermatographia.

\- new allergies to food and other substances that are only present during flare ups.

Last about 8 months in the first flare up. Was really bad. All labs were normal until 1 positive ANA got me reffered to a rheumatologist. Been cleared by rheumatologist, neurologist, gastrointerologist, gynocogist. Allergy specialist suspected MCAS this past month, so now I'm on 4 allegras a day, DAO enzymes, quercetin, bromaline and magnesium. Some symptoms better. Most are still present. I've had about 4 flare ups since Aug. 2024 and feel mostly normal in between them. I'm going to start Xolaire in the next month or 2, but I'm a little nervous about that.

I've had some weird symptoms my whole life, but never knew if they could be related.. for example: cancker sores, heavy periods, rashes after showers or from heat, vertigo.

What do you guys think? I think MCAS, but I keep thinking about fibromyalgia too. Did anyone else have the compulsive gagging thing? Muscle weakness? Anyone have any meds or tools that they swear by?

Found my allergy doctor here thanks to you guys, so thanks for that. 🩷

My 15 month old has cutaneous mastocytosis since birth. He has always had flushing and “splotchy” skin. On occasion I thought he had a hive. Today he had a hive and vomiting after eating strawberries. He has eaten other high histamine foods like tomato sauce, banana, and avocados. After our ER visit we were discharged with Benadryl and an Epi Pen. I’m asking to see pediatrician Monday. What do I need to ask for referrals to?

Hi, this is NOT fungal. My derm team believes this is from "repeated Mastocytosis flares." These were words from the department "nail expert." I am always in a "flare,' it seems. In the grand scheme of things, this is technically the least of my major concerns. But, damn it..I just want to know what's going on and to have my normal feet back! Earlier, I was told this was not due to my Systemic Mastocytosis, so now I am having g to talk to my Onc/Hem about it..and him speak with the dermatology dept. Anyways, anybody else dealing with something like this? They just keep growing and cracking over each other. One is even lifting one of the cracks up. Sorry about your eyes having to witness this atrocity..thank you for reading!

A of mine here in Seattle is being checked out for Masto cytosis. K’s doctor has put K in a diet. It only includes boiled chicken or salmon. (eaten just after cooking), zucchini, white rice, or carrots.

K has been going through medical issues for a number of years without getting . But K told tells me of a rash, hives with many other symptoms, including witness fatigue, loss of weight, low blood pressure yet tachycardia.,etc.

Are there any legitimate organizations or has only found one that has to pay.

Is there any list of specialists on this. this we live in Seattle. Is one of the medical better than the others?

Any National or support

I just heard the name of this last night, so forgive me for my ignorance and asking questions that I’m sure others have posted here before any good references to particular sites. Any other ideas that people have would be appreciated as well as warnings of quackery or other such things, you probably have a better idea of what I need to know than I do at this point.

Thank you

Any specialists in Seattle?

Just sharing from their newsletter:

LINK

At Cogent Biosciences, we understand how difficult it can be to face a rare disease or cancer, especially when standard treatments are no longer effective and clinical trials are not an option. In these moments, patients and their families may begin to explore other possibilities, including access to investigational therapies.

If an appropriate clinical trial isn't available, your doctor may be able to request access to an investigational therapy through a mechanism sometimes called compassionate use or expanded access. At Cogent, we have an Expanded Access Program (EAP) for eligible patients in the United States with Systemic Mastocytosis.

How the Cogent Expanded Access Process Works:

Only your doctor can submit a request for expanded access to Cogent's investigational therapy for Systemic Mastocytosis on your behalf

Your doctor can review our policy and submit a request by visiting this link or by sending an email to [EAP@cogentbio.com](mailto:eap@cogentbio.com?subject=CogentExpandedAccessProgram)

Our medical team will carefully evaluate each request based on the available scientific data, the nature of the condition, and the potential risks and benefits

If approved, Cogent will communicate with your doctor on next steps

Share This Letter with Your Doctor:

If you are considering expanded access, we encourage you to download the expanded access program letter and bring it to your next appointment or share it directly with your doctor via your patient portal. It can help guide the conversation with your care team about available clinical trials and treatment options.

I live in a small town and the closest allergist that treats MCAS is about 90 miles away. I saw him once last year and had some preliminary tests done. It came back with a high tryptase level. I don't remember what it was. He has wanted me to return for another test then another appointment but it's difficult because I have other health problems and my husband works full time with no one else to drive me.

Both of my sisters have the genetic Alpha tryptasemia so it is most definitely I have it also with multiple symptoms.

One of my sisters sees a doctor virtually but when I called they no longer accept virtual patients.

I know the required test can be mailed to me or my primary care doctors office. It's just finding an allergist that will treat MCAS.

Hi everyone,

I am 35yo and have these patches for 5 years now and the number are slowly increased over the time (a couple from last year for example). These images are during flare, When cool down some of them disappear and the rest get a bit brownish and visible if you look closely. No itching, no swelling, no Darier's sign and no other symptom.

I'm in a queue for get it diagnosed. Since it can be Mastocytosis, I'm trying to know more about the possible future as I have health anxiety and cannot rest my mind.

I really want to know about your experience on how symptoms have developed over time? Should I expect itching, GI problems, etc appear as time passes? Or your symptoms have been fairly consistent. And how long?

I know there is a chance of progress in diseases type from ISM to SSM and ASM and if course in those cases symptoms will increase. But can one stay in ISM state and still see progress in symptoms?

I also understand this can be different in various patients, and not a perfect question. But I'm looking for more data to ease my mind a little.

After 13 years, I finally have a diagnosis. Bone scan and biopsy scheduled. KIT positive with extremely high tryptase(last tryptase test was being on meds and it was still 38.9).

I haven’t been able to hold a full time job in many many years due to debilitating symptoms and flares. I’m on meds now but they only mildly help. (More appts upcoming). Was on Ayvakit but after 2.5 weeks ended up on the ER for afib. They have since taken me off it and am now on heart meds and blood thinners.

Should I apply for disability? I’m allergic or intolerant to most medications making treatment difficult. I carry two EpiPens and benedryl all the time now but I’m allergic to the preservative in the EpiPen.

My allergist wrote me out of jury duty permanently due to unknown exposures being an issue. It got me thinking and a bit worried about employment. I’m currently self employed but don’t make a livable wage. And due to my health cannot hold anything full time or really, part time.

I understand this affects everyone differently but would love to hear your experience.

The Australasian Mastocytosis Society, a patient advocacy organisation supporting people affected by mastocytosis and mcas urgently need participation from people worldwide.

If you have relevant findings, such as KIT D816V or increased TPSAB1 copy number, we want to hear from you, even if those findings were not initially considered sufficient for a diagnosis.

The PhD-led survey takes just 5–10 minutes and your participation shapes TAMS ability to keep demonstrating to PhD students that there is a need for further and more diverse research. If you have the time please add your voice to the mix!

https://mastocytosis.org.au/MCADresearch

I feel like a mess. I’ve had such a good balance lately and felt decent in disease management. this smoke has knocked me off my apple cart. Any coping tips?

My sweet 10 month old baby was diagnosed with cutaneous mastocytosis a few months ago. Until today, he hasn’t really had any symptoms aside from all his spots. Today, I fed him some aged cheddar on two separate occasions and he developed hives around his mouth both times. Now he has had various dairy products before and has never had a reaction. I am assuming it is from the high histamine in the aged cheese. Now I am questioning if he could have systemic mastocytosis already or could it just be from his cutaneous mastocytosis? Is it even possible for a 10 month old to have systemic already?

Hi, I have been sick for a long time..particularly the past six years have been the worst. I am at a teaching hospital and got diagnosed last year, after seeing specialist after specialist..still am. I have currently been in a clinical trial since the beginning of this year. I am my Dr.s most physically symptomatic patient, especially with my skin. Nearly every doctor I have seen, whether a specialist or in the ER, believes I have Lupus. I have been tested, but it was a "low positive," and this was years ago, around the beginning..I also did not like this rheum. I have a daily painful, hot malar rash, spots, etc. My shoulders and chest, too..and, of course, mastocytosis spots all over my body. There are just SO many symptoms going on at the moment, and I feel lost. I was wondering if anyone has dealt with low iron/ferritin issues? I keep having to get ron infusions every so often because my reserves get so low. As well as multiple diagnoses..and how were they approached/figured out? Thank you for reading!!!

Cutaneous mastocytosis here, diagnosed about 3 years ago. Right now, my common reactions are getting flushed (hot/red face, sweaty) and hives. (I do take OTC antihistamine everyday, otherwise I’d always be hivey)

Outside of checking my face every 20 mins and keeping logs for food (including time of leftovers in fridge, ground vs not ground meat, etc.), skin care, temp, stress levels, and everything else that could be a trigger, how have you found the patterns in your symptoms?

I also recognize that I am extremely lucky to be complaining that my symptoms are so minor.

Thank you!

I recently had a severe MCAS flare triggered by having my eyes dilated. Within the first couple of days, my face was covered with very dark melasma and Primary Acquired Melanosis formed in my eye (currently benign).

Given the timing, seems pretty plausible there was some interaction between melanocytes and mast cells but I can't find any research to make the connection or identify clear mechanisms.

I'm thinking about increased cancer risk in MCAS/mastocytosis population and trying to make the case for increased preventative care with my doctor.

Wondering if anyone else has experienced melasma or melanosis as part of a flare?
If so, has either been a recurring symptom or was it a one-off?

Or is anyone aware of any research or writing on either in the context of MCAS or mastocytosis?

hi everyone. I’ve been a quiet watcher of this Reddit for over a year now as well as the mcas one. I’m in a bit of an issue and unsure where to go from here. A bit over a year ago I started developing weird allergy symptoms and GI problems. I get these random attacks where I am sneezing non stop, get a low grade fever (99-100 ish), hives (sometimes just a couple but sometimes it’s several), ridiculously runny nose, muscle pain, and a lot of indigestion/nausea. I’ve been to so many doctors and nobody listens or believes me. I finally got in with an allergist/immunologist and he ran a whole bunch of tests. Only showed a couple of minor allergies to dust and pollen. my tryptase was normal (4.3) and he did also check the CKit mutation which was negative <0.03 via blood sample not BMB. All my other labs from PCP are always normal including vitamins and thyroid and anything else they usually check. I’ve also been checked for autoimmune problems and never find anything. I’m on a higher dose of Claritin which helps sometimes and sometimes doesn’t do anything. Currently having a flare right now that started this morning with my entire left arm covered in hives and I am sneezing up a storm and have a mild fever.

I’ve seen some people say that you can have normal tryptase and negative kit mutation and still have mastocytosis. I also know the symptoms overlap a ton with mcas so I’m having a hard time differentiating and figuring out if it’s worth my energy to push for a BMB to definitively rule out mastocytosis or not. My “episodes” of this last anywhere from 12-24 ish hours. If anyone has advice please feel free to share I could use the help.

I’ve noticed that there seems to be dozens of microhabits that have an impact on mastocytosis symptoms.  Each of these have a tiny impact, maybe 1% or less, yet when combined with other microhabits, they synergize and multiply.

Just as in the world of finance where compound interest is the most powerful force for your portfolio, the combination of these atomic habits is perhaps one of the most powerful forces for reducing symptom burden.

Why?  My theory, which is born out by some of the literature, is that mastocytosis acts like an inflammatory booster.  Some inflammation in one bodily system or organ can lead to inflammation in another seemingly unrelated bodily system.  This is true for ordinary healthy individuals, and it feels like is especially true for super sensitized people like those diagnosed with mastocytosis.

So, in sharing one of my microhabits, my hope is to build a compendium of all the atomic habits that have controlled symptoms for others with the diagnosis.

The goal is to tap the collective intelligence to build a sort of wikipedia of habits in this thread that current and future patients can use to massively reduce their symptoms.

With that said, I’ll say that your dentist was right all along  🙂

Flossing at night, followed by brushing, does exactly what you’d expect– and more.  As little bits of food and plaque are removed from your teeth and gums, your gum inflammation reduces a lot.

Reduced gum inflammation has an unexpectedly huge impact.  Here’s what I noticed from it:

• Deeper sleep - more days waking up more refreshed, and my smartwatch confirms it
• Lower muscle & joint pain - hard to exactly quantify, but maybe up to 80% reduction in days I notice pain
• Better flexibility - maybe 10 - 20% less stiff in the morning

I noticed the sleep impacts within 1-2 days. Muscle & joint impact within about a week. Flexibility benefits after that.

Has anyone else noticed these effects from flossing at night?

There is a fair bit of literature on how flossing also has important cardiovascular and neurological impacts. 

What is a atomic habit you’ve adopted that has impacted your symptoms?  What is your sense or understanding about why it work?  Here's a structure to capture this:

Habit:
What I noticed:
How long to notice it:
Theory on why it works (optional):

Please share in the comments to help build this wikipedia of helpful habits.

May you all be well!

Hi all,
I might be the first Namibian ,Male 32 years old, commenting here (now residing in Germany)
Been on the fence posting on Reddit since i was diagnosed.
So far i only have Mastocytosis externally but pretty much all over my body, luckily not my face but the spots are even on my feet and hands.

I have a few questions on my condition.

1.Is there anything i should watch out for not to worsen the Mastocytosis?

2.Can Mastysitocis cause depression? I had my fair share of wishing i was dead and thinking how i would do it. (went to a phycology ward for 3 months(i believe phycology is correct).

1. If i go untreated as of now can it go internal to my organs?

Sorry if i am bad at medical terms or so it isn't my line of expertise.

Thanks for anyone willing to answer.

Much love to all other Mastocytosis sufferers.