Has anyone developed MCAS since Covid?

BTW @djg3012 , @diverdown1 , @covidstinks2023 all- look at this: I just found this online TODAY!!
The Core Science: Mast Cells Express GLP-1 ReceptorsMechanism of Action: Peer-reviewed immunological data shows that human mast cells express GLP-1 receptors on their cellular surfaces.Stabilization Effect: When a GLP-1 receptor agonist (such as semaglutide) binds to these receptors, it acts as a direct mast cell stabilizer. It down-regulates the release of pro-inflammatory mediators, pro-inflammatory cytokines (like IL-6 and TNF-α), and systemic histamine.2. The Landmark July 2025 Case Series (Afrin, Weinstock, Dempsey)Study Citation: Afrin LB, Weinstock LB, Dempsey T, et al. "Utility of glucagon-like-peptide-1-receptor agonists in mast cell activation syndrome." The American Journal of the Medical Sciences.The Cohort: The study evaluated 47 patients with treatment-resistant, refractory MCAS who had failed conventional histamine-blockade therapy.The Efficacy Rate: An astounding 89% of MCAS patients demonstrated meaningful clinical benefit across a wide range of multisystem symptoms, including gastrointestinal inflammation, neurological flares, and profound fatigue.Clinical Observation: Many patients reported rapid, dramatic improvements in food tolerances and a reduction in localized GI pain within weeks of initiating therapy.

@jgk177 Thank you. I want to know more about this.

I feel for you...I had nearly the same symptoms post COVID 2020. I would put off eating because as soon as I did, I would fall asleep. I was suddenly allergic to dairy, gluten, and sugar, gaining weight from anything I did eat, out of breath with a short walk from the bedroom to the bathroom, racing pulse/blood pressure sporadically, severe fatigue, sensitivities to temperature, low blood oxygen, and more. I feel lucky that 6 years later I have about 50% of my life back. I do have to take an antihistamine every day to minimize the MCAS like symptoms, low dose naltrexone to manage the fatigue and pain, magnesium for leg cramps, and a vitamin D supplement to improve my sleep and immune system, I still have to watch my diet and still have to pace myself like crazy or I will run out of energy, But I am losing weight again and have slowly worked up to .7 of a mile of walking a day.

@vostie Just wow. I'm so sorry for your suffering and blown away that our symptoms seem to line up to the letter. I've also worked very hard, through a maze of medical failures and ever changing foods that bother me vs foods that don't. The weight gain made everything SO much harder, I finally found a doctor who was willing to write me a prescription for a GLP-1 because my weight shifted past over weight on the the verge of being obese.. that idiotic BMI chart still rules decisions. The GLP-1 has brought down the inflammation (at least for the first 3 days after a shot) so I can feel almost normal for 48 hours a week.. I'll take it for now. In the meantime I'm finally shedding some of the weight that makes me feel even more sluggish. I do feel the exhaustion and other symptoms (insomnia, red eyes, sensitive teeth, chills, sweats, etc) by day 4 after the shot, but I'm only in my second week. I have hope that aside from losing another 15 pounds, the meds will continue to tamp down the inflammation in my body everytime I eat. The ONLY way I can eat without falling asleep is if I eat 1/2 cup of food and not a bit more. Who can live like that? I mean I can when I'm home alone, but how do you do anywhere or do anything like that? I never gave up the gym because it's my mental health care.. if I had stopped working out, I don't think I'd still be here. But for sure I cannot do what I did 3 years ago before this started. I am trying to get into a Long Covid program in NYC, if I do, I will share whatever I learn here. Please take care of yourself!!

Thanks JGK...I am in several long covid support groups (over 1 million people in the USA alone) and am in the Scrippts LaJolla study on GLP1 for long covid. I sadly received the placebo, or am a GLP1 non-responder, but some of the other 1000 members of the study are feeling better. This study is using the GLP1 at the dosage schedule for diabetes but other studies are getting better numbers using micro dosing. I think when this study ends I will try the micro dosing to see if I can feel even better.

And I know what you mean about eating...I could fall asleep in a meeting if I ate just a little bit of food. That symptom is much better for me unless I have not paced myself. Then I eat and I sleep whether I want to or not.

@vostie I am JUST finding these support groups. I spent the past 3 years trying to navigate this alone. Live and learn. How did you get diagnosed with Long Covid and MCAS? I cannot find anyone locally who can offer much of anything on this.

@jgk177 I had to hire a concierge doctor. They charge you a monthly fee but you can see them for long appointments and can get an appointment in a day or two once you join the practice. She did not have experience with long covid but consulted with an expert here in Minnesota whose practice was full of long haulers. She had a long list of treatments to try and we just started checking them off.

MCAS was very hard to diagnose as few allergists here even try a diagnosis but with my mass cell load, it was easy when the right doctor was found. My concierge doc helped me with that as well as plenty of other referrals to specialists.

@vostie That is not surprising to hear at all. The fact that a person can spend thousands of dollars a year on health insurance and get sub par results is a huge part of this problem. Doctors don't have the time or the energy to "dig in" to anything that is out of very narrow list of aliments and as a result, millions of people suffer and never get the care they pay for, unless they can pay even more. I've been referred to THREE immunologists, none of whom test for MCAS. I now know before I even give them my last name, to ask first. The doctor that keeps referring me to people who can't help is a temp doctor in a practice I have been struggling with for almost 2 years. I recently tried to find a new PCP and the wait time is MINIMUM a year as a new patient. If not for the RD I have been working with for 2 years, (paying out of pocket) I would not even know what MCAS is.

Thank you for sharing your experience since COVID. Am truly sorry you have been going through so much as a result. I am in my 22nd month of long COVID. Have made good improvements. I do believe I have been dealing with MCAS, which may be connected with genetic issues that keep my body from breaking up histamine. Long COVID creates histamine, which causes higher levels of stomach acid, so it was compounding my genetic issues. I already took loratadine which is a H1 histamine blocker, quercetin, and two genetic supplements from Bob Miller of Tree of Life Health in Ephrata, PA, to help with the histamine/MCAS issues. Bob offers a genetic test that he then prints out a report from that shows what cellular problems you may have, and offers recommendations for genetic nutritional supplements that can help your cells to function more normally. Recently, I added famotadine (Pepcid) every 12 hours which is a H2 histamine blocker that also helps with the increased stomach acid issue, because I had read from multiple sources that taking this, along with the loratadine might help stop the long COVID internal tremors that started 4 months ago. My family doctor who is an Internist, allowed me to double the loratadine dose to 20mg. I take 10mg every 12 hours. I have been taking this protocol for 3 weeks and it has almost completely stopped the tremors. It has also stopped the hyperallergenic state I'd been in since having COVID, and the issues I was having in GI tract have stopped. I thought I'd share a link to a Dr. Leo Galland's in-depth paper on Long COVID Prevention and Treatment. It has GREAT information about MCAS, along with what he'd learned about the ACE2 enzyme and mitochondria's role in long COVID recovery. He is an Internist. I had gotten past Post Exertional Malaise but could only do so much activity before I'd have to stop and rest. Dr. Galland offers much information about supplements that can help with everything that he feels is involved in treating long COVID. I have added a Bioactive form of CoQ10, Ubiquinol, almost 2 weeks ago, to see if it would help with mitochondria function, and improve my strength, and lessen the fatigue. It HAS! I am able to do more activity now which I am so thankful for! Dr. Galland's paper also looks at the need to "re-establish a healthy gut microbiome" and there is an APPENDIX E with more information on that which may be helpful to you. Truly I learned so much and am still gleaning from all the information, and have sent my doctor his information and asked him to look at the Paper, since he'd already mentioned there may be problems with my mitochondria. Here is the link info to Dr. Galland's website. On the home page click the "long covid" tab, and then you scroll down to the bottom where you'll find the link to his "Complete White Paper / Long Covid: Prevention & Treatment": dr galland dot com (I can't put the actual website address or it won't let me send the comment to you.) Praying you, too, will find the information needed to regain your health, and be freed from the symptoms you've been dealing with.