Can you explain why seizures during Anaphylaxis happen? Does our Nervous System shutdown? Not enough oxygen to the brain? Preferably non-Epileptic as there is already enough information about those. When you have Autonomic or unknown seizures you’re looked at like you’re a mental patient. I only have seizures during Anaphylaxis and I’ve always been curious to know what happens during the reactions that they happen.

The specific mechanism by which anaphylaxis in a given patient can also cause seizure activity in the brain is unclear. It’s probably not even a matter of just a single such mechanism, and instead there likely are multiple mechanisms by which this can happen (for example, release of mediators from mast cells in the brain which can instigate unregulated neuronal excitation, or temporary impairment of blood flow to brain cells due to either constriction or dilation or cerebral blood vessels). I’m not clear as to what you mean by a “shutdown” of the nervous system, so I’m uncertain how to answer that part of the question; it strikes me that if the nervous system ever truly “shut down” (i.e., completely stop working), one would quickly die, but since people who suffer seizures rarely die from those seizures, the seizures can’t result from a “shutdown” of the patient’s nervous system. Furthermore, since seizures generally are due to *excessive* activity of the nervous system, that would seem to be the very opposite of a “shutdown” of the nervous system.

I agree it is regrettable (understandable, to be sure, but still regrettable) that many patients with mast cell disease are regarded as having solely a psychiatric issue and commonly are labeled as “hypochondriac,” “psychosomatic,” etc. It would be more productive, I think, for the doctor (and the patient’s other acquaintances and family) to simply acknowledge “we don’t know” what’s causing the patient’s problems rather than to reflexively assume the root of such a bizarre assortment of problems can only be psychiatric in nature, let alone to assume that the patient actually has control over such problems. However, until more physicians are taught about both mast cell disease and the value of acknowledging “we don’t know” (and, correspondingly, the dangers of assuming an unproven diagnosis), this will continue to be a difficult challenge for many patients with mast cell disease.


My EEG’s are also normal and I have strong Epilepsy in my family. My father has it and is passed down by the males in the family including my Great Grandfather, my Grandfather, Aunt, and Dad. My brother and I have been tested as well throughout our lives and we’re negative (thank God) but I still have Mast Cell seizures.

Although I don’t see a specific question in that paragraph, I think the fact that your EEGs are normal represents an opportunity to comment that although MCAS can drive true seizures, more commonly the seizure-like activity which sometimes *appears* to afflict MCAS patients is *not* from true seizures (as can easily be proven with EEG (electroencephalogram) tests) and instead is “pseudo-seizure” activity likely representing flares of mast cell activation impacting the autonomic nervous system.


My question is about reacting to antihistamines you could once use. I am also running out of rescue meds and taking and increasing current H1/H2’s along with other MCAS stabilizers. Are there any antihistamine families with less risk of developing reactions or is it solely based on each individual? I am becoming dependent on Epi pens although their side effects are extreme and render the remainder of the day, and sometimes into the next day, a write-off. Are there consequences to using epinephrine frequently or long term?

The responses in MCAS patients to particular medication products are highly individualized.

Although it’s possible for an MCAS patient to react to any given drug, in my experience most adverse reactions suffered by most MCAS patients to most medication products are reactions by the patient’s dysfunctional mast cells directed *not* against the drugs in those medication products but rather to one or more of the excipients (fillers, binders, dyes, preservatives) in those products. Therefore, if a drug which previously appeared to be helping in a given fashion is no longer helping as well, or at all, then the two scenarios which need to be considered are (1) the disease has fundamentally transformed to become resistant to that drug, or – more likely – (2) the formulation of the drug has changed and now includes a triggering excipient. Sometimes a change in formulation is obvious – for example, switching from one over-the-counter brand to another – but sometimes such a change is anything but obvious.

For example, a pharmacist may substitute one little round pill for another little round pill of identical shape, size, color, and taste – and yet even though both pills would contain the same drug (i.e., the same active ingredient), they could still *easily* contain different excipients. (As an even more specific example, most patients seem unaware that many “white” pills actually contain dyes – red, blue, and otherwise – which one might understandably assume wouldn’t be in such products, and yet dyes of one color often are found in products which appear to be of another color entirely. Until one checks the full ingredient list of a medication product, one can’t know what’s truly in it. And there are even occasional examples of medication products inadvertently containing ingredients not listed on the ingredients label.

One has to be even *more* careful with “supplements” as opposed to “drugs,” at least in the United States, since U.S. law requires drug manufacturers to provide a label listing all the ingredients in the product they’re aware of, while there are far less stringent requirements placed upon supplement manufacturers.) MCAS patients who find themselves doing worse fairly suddenly after transitioning from an old medication product (or supplement product!) supply to a new supply (such as a refill) need to carefully consider (and potentially even discuss with their pharmacists) the possibility that the medication formulation might have changed and might be newly exposing the patient to a triggering excipient.

I don’t know of any particular “antihistamine families” which are less likely to provoke reactions than others. In general, H1 and H2 blockers are extraordinarily well-tolerated drugs, and it’s far more likely that an adverse reaction to an H1 or H2 blocker is an excipient-directed reaction rather than a reaction directed against the actual H1 or H2 blocker drug itself.

Epinephrine is a potent natural substance and thus a potent drug. There have long been recognized many potential adverse reactions to epinephrine (for example, heart racing or a headache, or even a heart attack or stroke), but nevertheless, when one is having anaphylaxis, epinephrine is usually the “best” drug to take (“best” obviously meaning the best *balance* of positive effects against negative effects). It should be noted, though, that most epinephrine autoinjectors contain a “metabisulfite” preservative, which can be a trigger of mast cell activation in some (fortunately relatively few) mast cell patients. When such a situation is identified, it calls for use of preservative-free epinephrine to treat anaphylaxis, and such sources of epinephrine are available but obviously have shorter “shelf-life” than preservative-containing formulations.

Some MCAS patients – especially those who, for various reasons, must use “beta blocker” drugs (a drug class generally to be avoided in MCAS because of its ability to interfere with epinephrine’s ability to work) – find that glucagon can be an effective alternative to epinephrine, and glucagon autoinjectors are available (though again the preservative issue needs to be acknowledged).


My question is about a negative biopsy for mast cells of the esophagus, stomach and duodenum. Can you still have GI complications or be in GI failure, considered to be a result of MCAS, with the negatives biopsies? How would you explain the effects of MCAS in this situation?

It must be kept in mind that MCAS is, far and away, an issue of improper *activation* of (at least some portion of) the body’s mast cells, and that even if increased *numbers* of mast cells can be found in one tissue or another in an MCAS patient, such increases usually are modest, and it is virtually never the *number* of mast cells which is a clinically significant problem in MCAS patients. The clinically significant problems in MCAS arise almost exclusively from the improper activation of mast cells.

As such, it’s easily possible to have “negative biopsies” for mast cells in any particular organ system and still have problems arise in that organ system as a consequence of improper *activation* of mast cells (including both mast cells located directly in that organ system as well as distantly located mast cells, which might be releasing *mediators* which could come – directly or indirectly – to have impacts on organ systems far away from the mast cells from which they were released). I have seen many cases in which it is clear that dysfunctional mast cells in one part of the body (for example, the GI tract) have had adverse effects on distantly located organ systems (for example, the brain or the bone marrow), and once one controls the dysfunctional mast cells causing those distant effects, then the distant effects improve.


Is there a higher probability of getting a bone marrow disorder or blood cancer/leukemia with an MCAD diagnosis? Is there a specific gene associated with this?

Unfortunately, it does appear to be the case that MCAD confers some increased risk for blood cancers (including leukemia and other types of blood cancers), but it remains impossible to predict which MCAD patients will develop such cancers. That said, it also appears to be the case that when a blood cancer develops in a patient who also has mast cell disease, concurrent treatment of both the blood cancer and the mast cell disease seems to yield a better outcome than if only the blood cancer were treated.

Different blood cancers have been found to have different genes associated with them. This is quite a complicated topic (about which many entire textbooks have been written) and is well beyond the scope of this forum. The KIT gene which is commonly mutated in various forms of mast cell disease is also occasionally found mutated in certain other forms of blood cancer.


Can multiple non-cancerous thyroid nodules and co-occurring cysts on the ovaries be caused by MCAD?

As noted previously, MCAD/MCAS is a disease which generally features chronic inappropriate inflammation +/- allergic-type phenomena +/- abnormalities in growth/development in potentially any tissue. As such, yes, the abnormal growths you described in your question can be seen in MCAD/MCAS. In fact, in my experience, the sorts of growth abnormalities you listed are quite common in MCAD/MCAS patients.

If you have additional questions on Mast Cell Activation Syndrome (MCAS), be sure to leave them on our MCAS Facebook page here. We will be putting out a new blog post every Friday answering a batch of randomly selected questions posted on our Facebook page.

If you would like to see a NY Mast Cell Activation Disorder specialist, Dr. Lawrence Afrin is now seeing patients in a private practice setting at our office in Armonk, NY. To make an appointment with Dr. Afrin, please call the office or contact us here