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The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 46

56. Why do I react every time I eat?

When you swallow food, your nervous system sends signals to tell the cells in the stomach that food is on the way. As a result of this neurologic signal, hormones are released to tell your stomach to get ready to digest. These hormones cause histamine to be released by cells in the stomach. The histamine tells your stomach to make acid to digest your food. Solid food is more activating to the stomach in this way than liquids are.

This is a normal function of the body and happens in everyone, not just people with mast cell disease. However, histamine released in the stomach can activate mast cells and cause typical mast cell symptoms. Like everything else in mast cell disease, how much this affects patients varies a lot. But something to keep in mind is that a lot of mast cell patients who are “allergic to everything they eat” are actually reacting to the normal histamine release that contributes to digestion. They are essentially allergic not just to what they are eating, but to the process of eating.

57. Do I have to go to the hospital every time I use an epipen?

Unless you have received very explicit instructions not to do so from a health care provider that is familiar with the particulars of your life and your health, you need to go to the hospital every time you use an epipen. The reason for this is because an epipen is a temporary measure. The purpose of the epipen is to give you time to get to a hospital for more advanced care. Epinephrine is broken down by your body in a matter of minutes so it only provides a small window of protection. While many patients only need one epipen, there is no way to know if you will have another wave of anaphylaxis after the first one. Additionally, many patients require other medications and IV fluids to treat anaphylaxis. These can be provided at a hospital.

The reason you have to go to the hospital is to give you access to more comprehensive care, not because using an epipen is dangerous.

The Provider Primers Series: Medications that impact mast cell degranulation and anaphylaxis

A number of medications can induce mast cell degranulation and histamine release. Other medications increase the risk of anaphylaxis and can increase the severity of anaphylaxis.

Medication reaction profile is very individual and not all mast cell patients react to the medications listed below. Additionally, there may be a need for some mast cell patients to take  medications listed below if the benefit outweighs the risk.

Medications that are reported to induce mast cell degranulation and histamine release
Alcohol[i] Amphoterecin B[ii] Aspirin[i] Atracurium[iii]
Caine anesthetics (esters)[iv] Codeine[v] Colistin (polymyxin E)[vi] Dextran[iii]
Dextromethorphan[iii] Gelatine[iii] Iodine based radiographic dye[vii] Meperidine[viii]
Miconazole[ix] Mivacurium[iii] Morphine[iv] Nefopam[iii]
NSAIDs[x] Phentolamine[xi] Polymyxin B[v] Reserpine[xii]
Rocuronium[iv] Succinylcholine[iv][xiii] Thiopental[iv] Tolazoline[v]
Vancomycin[xiv] (especially when given intravenously)


Patients on beta blockers are more likely to experience anaphylaxis and more likely for that anaphylaxis to be severe and treatment resistant. Beta blockers also impede treatment of anaphylaxis by interfering with the action of epinephrine[xvi]. Patients at risk for anaphylaxis who are on beta blockers should get a glucagon pen to use prior to epinephrine[xv].

Beta adrenergic blockers[xvi] (Note: List is not exhaustive)
Acebutolol Atenolol Betaxolol Bisoprolol
Bucindolol Butaxamine Cartelol Carvedilol
Celiprolol Esmolol Metoprolol Nadolol
Nebivolol Oxprenolol Penbutolol Pindolol
Propranolol Sotalol Timolol


Alpha blockers impede treatment of anaphylaxis by interfering with the action of epinephrine[xvii].

Alpha-1 adrenergic blockers[xvii] (Note: List is not exhaustive)
Alfuzosin Amitryptiline Amoxapine Atiprosin
Carvedilol Chlorpromazine Clomipramine Clozapine
Dapiprazole Dihydroergotamine Doxazosin Doxepin
Ergotamine Etoperidone Fluphenazine Hydroxyzine
Imipramine Labetalol Loxapine Mianserin
Nefazodone Olanzapine Phentolamine Prazosin
Quetiapine Risperidone Silodosin Tamsulosin
Thimipramine Thioridazine Trazodone


Alpha-2 adrenergic blockers[xvii] (Note: List is not exhaustive)
Buspirone Chlorpromazine Clozapine Esmirtazapine
Fluophenazine Idazoxan Loxapine Lurasidone
Mianserin Mirtazapine Olanzapine Phentolamine
Risperidone Thioridazine Yohimbe

Patients on angiotensin-converting enzyme (ACE) inhibitors are also more likely to experience anaphylaxis and more likely for that anaphylaxis to be severe and treatment resistant. The exact reason for this is unclear but ACE inhibitors impede appropriate bradykinin metabolism which may contribute to anaphylaxis[xvi].

Angiotensin converting enzyme (ACE) inhibitors[xvi] (Note: List is not exhaustive)
Benazopril Captopril Enalapril Fosinopril
Lisinopril Moexipril Perindopril Quinapril
Ramipril Trandolopril

Special notes:

Aspirin use in mast cell patients to suppress prostaglandin production is becoming increasingly common[xviii]. In some situations, other NSAIDs are also used.

Fentanyl, sufentanil, remifentanil and alfentanil are the preferred opioids for mast cell patientsiv. Hydromorphone releases minimal histamine and is also used in mast cell patients.[xix]


[i] Valent P. (2014). Risk factors and management of severe life-threatening anaphylaxis in patients with clonal mast cell disorders. Clinical & Experimental Allergy, 44, 914-920.

[ii] Lange M, et al. (2012). Mastocytosis in children and adults: clinical disease heterogeneity. Arch Med Sci, 8(3), 533-541.

[iii] Dewachter P, et al. (2014). Perioperative management of patients with mastocytosis. Anesthesiology, 120, 753-759.

[iv] Eggleston ST, Lush LW. (1996). Understanding allergic reactions to local anesthetics. Ann Pharmacother, 30(7-8), 851-857.

[v] Brockow K, Bonadonna P. (2012). Drug allergy in mast cell disease. Curr Opin Allergy Clin Immunol, 12, 354-360.

[vi] Kwa A, et al. (2014). Polymyxin B: similarities to and differences from colistin (polymyxin E). Expert Review of Anti-infective Therapy, 5(5), 811-821.

[vii] Kun T, Jakubowski L. (2012). Pol J Radiol, 77(3), 19-24.

[viii] Blunk JA, et al. (2004). Opioid-induced mast cell activation and vascular responses is not mediated by mu-opioid receptors: an in vivo microdialysis study in human skin. Anesth Analq, 98(2), 364-370.

[ix] Toyoguchi T, et al. (2000). Histamine release induced by antimicrobial agents and effects of antimicrobial agents on vancomycin-induced histamine release from rat peritoneal mast cells.  Pharm Pharmacol, 52(3), 327-331.

[x] Grosman N. (2007). Comparison of the influence of NSAIDs with different COX-selectivity on histamine release from mast cells isolated from naïve and sensitized rats. International Immunopharmacology, 7(4), 532-540.

[xi] Powell JR, Shamel LB. (1979). Interaction of imidazoline alpha-adrenergic receptor antagonists with histamine receptors. J Cardiovasc Pharmacol, 1(6), 633-640.

[xii] Muroi N, et al. (1991). Effect of reserpine on histamine metabolism in the muse brain. J Pharmacol Exp Ther, 256(3), 967-972.

[xiii] Sadleir PH, et al. (2013). Anaphylaxis to neuromuscular blocking drugs : incidence and cross-reactivity in Western Australia from 2002 to 2011. Br J Anaesth, 110(6), 981-987.

[xiv] Sanchez-Borges M, et al. (2013). Hypersensitivity reactions to non beta-lactam antimicrobial agents, a statement of the WAO special committee on drug allergy. World Allergy Organization Journal, 6(18), doi:10.1186/1939-4551-6-18

[xv] Thomas M, Crawford I. (2005). Glucagon infusion in refractory anaphylactic shock in patients on beta-blockers. Emerg Med J, 22(4), 272-273.

[xvi] Lieberman P, Simons FER. (2015). Anaphylaxis and cardiovascular disease: therapeutic dilemmas. Clinical & Experimental Allergy, 45, 1288-1295.

[xvii] Higuchi H, et al.(2014). Hemodynamic changes by drug interaction of adrenaline with chlorpromazine. Anesth Prog, 61(4), 150-154.

[xviii] Cardet JC, et al. (2013). Immunology and clinical manifestations of non-clonal mast cell activation syndrome. Curr Allergy Asthma Rep, 13(1), 10-18.

[xix] Guedes AG, et al. (2007). Comparison of plasma histamine levels after intravenous administration of hydromorphone and morphine in dogs. J Vet Pharmacol Ther, 30(6), 516-522.

The price of surviving anaphylaxis

Anaphylaxis is a severe, multisystem allergic event. It is a medical emergency and can be fatal. A 2015 WAO update stated that Americans have a 1.6% risk of anaphylaxis over the course of their lifetime. In the US, anaphylaxis was fatal in 186-225 patients annually, a frequency of 0.63-0.76 per million people. 30-43% of patients with a history of anaphylaxis will have a recurrence.

Epinephrine is the only drug known to decrease the incidence of death from anaphylaxis and should be administered as the first-line agent. Delay in administration of epinephrine has been shown to directly increase the risk of death from anaphylaxis. The use of epinephrine autoinjectors by patients at risk of anaphylaxis is critically important to managing patient safety. Despite this, many patients do not have or do not use their epinephrine autoinjectors.

The use of epinephrine autoinjectors in anaphylaxis has been very well studied. A 2014 paper by Wood and colleagues reported the findings from surveying 35,079 patients. They found that 60% of patients did not have an epinephrine autoinjector on their person when anaphylaxis recurred. Another study by Sanchez found 9-28% of patients carried autoinjectors.

Wood found that 52% of patients with a history of anaphylaxis were never prescribed an autoinjector. In a patient group of 261 with history of proven anaphylaxis, a mere 11% used the autoinjector for their most recent anaphylactic event. Not using epinephrine in the appropriate time frame can have grave consequences. In anaphylaxis patients who progressed to cardiac arrest, 67% did not receive epinephrine within an hour of onset. Among patients who died from anaphylaxis, none of them received epinephrine when the first symptoms presented. Only 14% of fatal anaphylaxis patients were administered epinephrine prior to cardiac arrest.

In many instances, economics is to blame for not carrying an epinephrine autoinjector. A truly stunning statistic is that 50% of anaphylaxis patients do not fill prescriptions for autoinjectors once the cost is over $300. In the previously mentioned 2014 Wood publication, 41% of anaphylaxis patients reported a household income of less than $50,000. Despite being uniformly accepted as a medication used to prevent death and severe complications resulting from anaphylaxis, epinephrine autoinjectors are often not classified by insurance companies as a preventative medication. An analysis of American insurance plans found that the two pack of Epipens was classified as a tier 1 or 2 medication in 67% plans; tier 3 or 4 in 6% plans; “approved” without any contribution to the cost of the drug in 5% of plans; and 22% plans did not cover Epipens at all.

A 2012 paper assessed how patient cost related to adherence to treatment recommended by their provider for a wide array of conditions. Eaddy reported that of the 66 studies evaluated 85% (56 studies) demonstrated that patients were less likely to adhere to the treatment plan when their costs increased.  High out-of-pocket costs were definitively shown to decrease patient use of preventative health care measures, resulting in poorer outcomes.  Increasing copays and deductibles impede access to life saving medication for anaphylaxis patients. If epinephrine autoinjectors were classified universally as preventative medications, insurance companies would be obligated to fully cover the associated costs. They would also be prevented from requiring patients to pay large out of pocket costs for autoinjectors as contribution to deductibles.

Kaplan reported that only 11% of patients with a history of anaphylaxis refill their epinephrine autoinjectors as needed. Instead, many patients rely on expired autoinjectors. Epinephrine is an inherently unstable molecule that degrades quickly when exposed to oxygen or light. A study in 2000 showed that while autoinjectors still functioned as intended up to 90 months after expiration, epinephrine concentration was significantly reduced. Still, expired epinephrine is still better than no epinephrine in the event of anaphylaxis as the benefit would outweigh the risk.

Epinephrine autoinjectors are designed to be stored at 20-25°C but tolerate occasional exposure to higher or lower temperatures in the range of 15-30°C. While heat is known to hasten degradation of epinephrine, freezing apparently is not. The 2015 WAO update mentioned that if autoinjectors are frozen, epinephrine concentration is not affected and that patients can use them as long as they are completely thawed. (I find this really wild, I had never heard of this before.)

Exorbitant costs prevent anaphylaxis patients from having ready access to epinephrine autoinjectors, the only first line medication for anaphylaxis. 50% of patients do not fill prescriptions for epinephrine autoinjectors when their cost is over $300. With the cost of autoinjectors well into the hundreds of dollars for many patients, millions of people in the US may be unable to afford this lifesaving medication for which is there is no alternative.


Simons FER, et al. 2015 update of the evidence base: World Allergy Organization anaphylaxis guidelines. World Allergy Organization Journal 2015: 8(32).

Wood RA, et al. Anaphylaxis in America The prevalence and characteristics of anaphylaxis in the United States. J Allergy Clin Immunol 2014: 133, 461-467.

Noimark L, et al. The use of adrenaline autoinjectors by children and teenagers. Clinical & Experimental Allergy 2012: 42(2), 284-292. Eaddy MT, et al. How patient cost-sharing trends affect adherence and outcomes. Pharmacy & Therapeutics 2012: 37(1), 45-55.

Simons FER, et al. Outdated EpiPen and EpiPen Jr autoinjectors: Past their prime? J Allergy Clin Immunol 2000: 105(5), 1025-1030.

Sanchez J. Anaphylaxis. How often patients carry epinephrine in real life? Rev Alerg Mex 2013: 60, 168-171.

Kaplan MS, et al. Epinephrine autoinjector refill history in an HMO. Curr Allergy Asthma Rep 2011: 11, 65-70.)

Kim JS, et al. Parental use of EpiPen for children with food allergies. J Allergy Clin Immunol 2005: 116(1), 164-168.


No, using the manual syringe/vial method is NOT the same as using an epinephrine autoinjector

I have a lot of inflammatory things to say about the current economic situation for patients who need epinephrine autoinjectors but for now, I’m going to stick to dispelling the most damaging myth I have seen spreading like wildfire.

No, manually drawing epinephrine from a vial or ampule into a syringe and then administering is NOT the same as using an autoinjector.

The American Academy of Allergy, Asthma & Immunology is a professional organization that regularly publishes updated practice parameters on the treatment of anaphylaxis. In their 2015 Anaphylaxis Practice Parameter Update, the AAAAI recommended that providers “prescribe two doses of auto-injectable epinephrine for patients who have experienced an anaphylactic reaction and for those at risk for severe anaphylaxis.”

This publication also addresses commonly disputed situations relating to anaphylaxis such as when and how to administer epinephrine to patients in special populations, like children under the weight range for Epipen Jr (33 pounds). The recommendation in the practice parameter was to use an Epipen Jr rather prescribe a syringe and vial of epinephrine for the parents to administer a smaller dose. The justification for this recommendation given in the 2015 Anaphylaxis Practice Parameter Update is that “…underdosing might not effectively treat anaphylaxis, giving a dose that is slightly above the ideal dose appears to be a better option than giving a dose that is below the recommended dose.”

A 2001 study by Simons et al. assessed how long it takes parents to manually draw up epinephrine from a vial. They also determined how long this took for resident physicians, general duty nurses and ER nurses. The results are in table 1 below.

Table 1: Mean time to draw up dose of epinephrine, range of time and variation in drug concentration
Group Mean time to draw up dose Range of time Variation in epinephrine content within group
Parents 142 ± 13 seconds 83-248 seconds Forty-fold variation
Resident physicians 52 ± 3 seconds 30-83 seconds 7 to 8-fold variation
General duty nurses 40 ± 2 seconds 26-71 seconds 2-fold variation
ER nurses 29 ± 0.09 seconds 27-33 seconds No variation


As you can see, the fastest parent drew it up in 83 seconds (about a minute and a half) while the slowest drew it up in 248 seconds (over four minutes). There was a 40-fold variation in the amount of epinephrine drawn up so both underdosing (which will not stop anaphylaxis) and overdosing (which can cause severe CV effects) would have occurred. Please note that this study does not assess how much longer it took to inject the medication for obvious reasons. It was also done in a controlled environment that assuredly was much less stressful and chaotic than one that would accompany a real life anaphylactic emergency.

Say it takes 15 seconds to find the vial and needle and open them and another 15 seconds to inject it. In a best case scenario, in which the parent is aware of anaphylaxis at the exact moment it begins, is in no way flustered, confused, or scared, and is in a situation where they can immediately respond (by which I mean, they are not driving, they are not swimming, they are not watching their child from 100 feet away), the fastest a parent would be able to draw it up and administer the med would be about two and a half minutes. Two and a half minutes with no oxygen if the child’s airway closes right away. If you are an anaphylaxis patient and are trying to do this for yourself, you would be expected to be able to function without oxygen for two and a half minutes.

About 30% of anaphylaxis patients require a redose of epinephrine to control anaphylaxis. So if you or your child is one of those people, you then have to do all of this again. If the first dose doesn’t do much, it could be another two and a half minutes.

The numbers were better for resident physicians and general duty nurses but you are still looking at 2-2.5 minutes for the slower members of these groups. There was a 7 to 8-fold difference in amount of medication drawn by resident physicians. ER nurses reliably drew up the dose in about 30 seconds and assuming that it takes 30 seconds to get the med and needle, and to inject it, they could draw and deliver in about a minute. That is the best you can hope for.

I realize that many mast cell parents and patients draw from vials/push meds/inject meds frequently and they may be practiced enough to draw the dose reliably and administer correctly. If we assume the most competent among them to be as competent as the ER nurses, it takes about a minute to administer the med. I just timed myself and it took eight seconds for me to get the epipens out of my purse, open the case, and remove the blue cap. (I used a trainer). It took less than one second to bring the injector to my leg. The entirety of the dose of epinephrine is delivered from an epipen in three seconds.  So 12 seconds for use of an epipen vs 60 seconds for the fastest, most reliable manual draw and inject.

There are currently two other autoinjectors available in the US: Adrenaclick and epinephrine autoinjector, a generic version. Both of those autoinjectors differ from epipens in two important ways: they are syringe based, whereas epipens are cartridge based; and their needles are shorter compared to epipens. In one specific comparison study by Ram et al., Epipens were found to more reliably deliver the most epinephrine (74.3% of intended dose) compared to syringe autoinjectors like Adrenaclick and epinephrine autoinjector (25.7% of intended dose). Auvi-Q was pulled off the market for similar delivery issues. (Author’s note: please note that this study did not include the specific generic epinephrine autoinjector, but its delivery mechanism is comparable to Adrenaclick).

A 2015 study reported by Umasunthar and colleagues compared how often mothers of food allergic children were able to correctly administer Anapen (a syringe based autoinjector not available in the US) vs Epipen in a simulation. Six weeks after they were shown how to use it, 42% correctly administered Anapen and 43% correctly administered Epipen. This means that over half of participants could not correctly administer epinephrine even with an autoinjector.

Alternative autoinjectors are not comparable to Epipens and neither is the manual syringe/vial method.  Delay in administration of epinephrine is a strong risk factor for poor outcome, including fatal anaphylaxis. Additionally, delay in administration of epinephrine or inadequate initial dosing is a risk factor for biphasic anaphylaxis.

Stay safe out there.


Lieberman P, et al. Anaphylaxis – a practice parameter update 2015. Ann Allergy Asthma Immunol 2015: 115, 341-384.

Lieberman P. Biphasic anaphylactic reactions. Ann Allergy Asthma Immunol 2005: 95, 217-228.

Ram FSF, et al. Epinephrine self-administration in anaphylactic emergencies: Comparison of commonly available autoinjectors. Journal of Asthma and Allergy Educators 2012: 3(4), 178-181.

Simons FER, et al. Epinephrine for the out-of-hospital (first-aid) treatment of anaphylaxis in infants: Is the ampule/syringe/needle method practical? Journal of Allergy and Clinical Immunology 2001: 108(6), 1040-1044.

Umasunthar T, et al. Patients’ ability to treat anaphylaxis using adrenaline autoinjectors: a randomized controlled trials. Allergy 2015: 70(7), 855-863.

Interplay between mast cells and hormones: Part 3 of 8

Hormone Location released Major functions Interaction with mast cells Reference
Dopamine Hypothalamus

Adrenal gland (medulla)

Inhibit prolactin released from pituitary

Increase heart rate and blood pressure

Inhibit norepinephrine release



Enhances mast cell degranulation

Perpetuates immediate and late phase hypersensitivity reactions

H3 receptor activation inhibits dopamine production

Dopamine is released by mast cells

H1 inverse agonists increase dopamine release

Histamine increases dopamine release

Mori T, et al. D1-like dopamine receptors antagonist inhibits cutaneous immune reactions mediated by Th2 and mast cells. Journal of Dermatological Science 2013: 71, 37-44.

Xue L, et al. The effects of D3R on TLR4 signaling involved in the regulation of METH-mediated mast cell activation. International Immunopharmacology 2016: 36. 187-198.

Endothelin Stomach Promotes smooth muscle contraction of stomach

Very potent vasoconstrictor

Activates mucosal mast cells

Mast cells regulate endothelin levels to prevent loss of blood flow to tissues

Boros M, et al. Endothelin-1 induces mucosal mast cell degranulation and tissue injury via ETA receptors. Clin Sci (Lond) 2007: 103(48), 31S-34S.

Hultner L, Ehrenreich H. Mast cells and endothelin-1: a life-saving biological liaison. Trends Immunol 2005: 26(5), 235-238.


Epinephrine/ adrenaline Adrenal gland (medulla), sympathetic nervous system Fight or flight response

Increases heart rate, force of heart contraction, blood pressure, energy breakdown, production of ACTH, bloodflow and energy to the brain and muscles

Suppresses nonessential functions and significantly decreases GI motility and excretion of urine and stool

Epinephrine inhibits IgE mediated released of histamine, prostaglandins and TNF

Epinephrine inhibits mast cell proliferation, adhesion and movement within the body SCF reduces action of epinephrine on mast cells by decreasing B2 adrenergic receptors



Cruse G, et al. Counterregulation of beta(2)-adrenoceptor function in human mast cells by stem cell factor. J Allergy Clin Immunol 2010: 125(1), 257-263.

Scanzano A, Cosentino M. Adrenergic regulation of innate immunity: a review. Front Pharmacol 2015.

Erythropoietin Kidney Stimulate red blood cell production

Protects nerve cells and tissues

During low oxygen events, mast cells express receptors for erythropoietin

Erythropoietin can bind at the CKIT receptor

Decreases inflammatory response to infection (decreases IL-6 and TNF)

Wiedenmann T, et al. Erythropoietin acts as an anti-inflammatory signal on murine mast cells. Mol Immunol 2015: 65(1), 68-76.
Estradiol and other estrogens Ovaries, placenta, adipose tissue, testes Drive female secondary sex characteristics

Increase metabolism, uterine and endometrial growth, bone production, and the release of cholesterol in bile

Increase production of proteins in liver, cortisol, sex hormone binding globulin, somatostatin, clotting factors II, VII, IX, X, antithrombin III and plasminogen, HDL, triglycerides

Decrease LDL, production of adipose tissue, GI motility



Modulate salt and water retention

Inhibits programmed cell death of germ cells

E2 is a very potent mast cell degranulator

E2 drives mast cell degranulation in ovaries to trigger ovulation

Enhances IgE mediated degranulation

Increased production of leukotrienes

Increases mast cell density in ovaries

Zaitsu M, et al. Estradiol activates mast cells via a non-genomic estrogen receptor-a and calcium influx. Mol Immunol 2007: 44(8), 1977-1985.

Zierau O, et al. Role of female sex hormones, estradiol and progesterone, in mast cell behavior. Front Immunol 2012: 3, 169.

Follicle stimulating hormone (FSH) Pituitary Stimulates maturation of ovarian follicles

Stimulates maturation of seminiferous tubules, production of sperm and production of androgen binding protein

Triggers mast cell degranulation

Increases mast cell density in ovaries

Theoharides TC, Stewart JM. Genitourinary mast cells and survival. Transl Androl Urol 2015: 4(5), 579-586.

Jaiswal K, Krishna A. Effects of hormones on the number, distribution and degranulation of mast cells in the ovarian complex of mice. Acta Physiol Hung 1996: 84(2), 183-190.

Gastric inhibitory polypeptide/ glucose-dependent insulinotropic polypeptide (GIP) Duodenum, jejunum Triggers release of insulin

Involved in fatty acid metabolism

Involved in bone formation

May suppress release of stomach acid triggered by histamine McIntosh CHS, et al. Chapter 15 Glucose-Dependent Insulinotropic Polypeptide (Gastric Inhibitory Polypeptide; GIP). Vitamins & Hormones 2009: 80, 409-471.
Gastrin Stomach, duodenum, pancreas Release of gastric acid

Release of pepsinogen, the precursor to pepsin

Triggers secretion of pancreatic enzyme

Triggers emptying of gallbladder

Increases stomach motility

Triggers release of histamine in enterochromaffin-like cells to trigger gastric acid secretion

Triggers mast cell degranulation

Gastrin releasing peptide, which induces gastrin release, triggers histaminergic itching response

Akiyama T, et al. Roles of glutamate, substance P, and gastrin-releasing peptide as spinal neurotransmitters of histaminergic and nonhistaminergic itch. Pain 2014: 155, 80-92.


Anaphylaxis and mast cell reactions

Author’s note: I am not a medical doctor. Anaphylaxis and use of epinephrine must be discussed with the managing provider to determine the best treatment plan for any individual patient.


Determination of mast cell reaction vs anaphylaxis

Anaphylaxis has a very complicated relationship with mast cell disease. Mast cell symptoms and reactions are inherent parts of mast cell disease.  All mast cell patients can reasonably expect to have some mast cell symptoms as part of their baseline.

Anaphylaxis is not an inherent part of mast cell disease. Anaphylaxis is a complication of mast cell disease.  Mast cell patients are at increased risk for anaphylaxis, but not all mast cell patients experience anaphylaxis.  In some studies, as many as 50% of mast cell patients had never experienced anaphylaxis.

The fact that anaphylaxis and mast cell reactions can have the same symptoms is probably the reason why it is difficult to separate the two. So for a minute, let’s stop talking about mast cell disease and consider a similar scenario that is better described.

  • Coronary artery disease (CAD) is the leading cause of death worldwide. It affects millions of people around the world. Everyone knows someone with coronary artery disease.  Probably multiple someones.
  • Patients with CAD have narrow arteries that interfere with blood flow to the heart. When they are diagnosed with CAD, their provider will tell them about symptoms they may experience daily as a normal part of their disease.  Their provider will also tell them about symptoms that they may experience that indicate the heart is not getting enough oxygen, like radiating chest pain, shortness of breath and nausea.  In these scenarios, the patient needs to take a med like nitroglycerin to try and stop the episode.  If that doesn’t work, the patient is at risk for a heart attack.
  • Radiating chest pain, shortness of breath and nausea are symptoms of CAD. Heart attack is not a symptom of CAD.  It is a complication of CAD.  It can also present with the same symptoms of radiating chest pain, shortness of breath and nausea.

Flushing, nausea, diarrhea and hives are symptoms of mast cell disease. (I’m just using these as examples, there are many others).  Anaphylaxis is not a symptom of mast cell disease.  It is a complication of mast cell disease.  It can also present with the same symptoms of flushing, nausea, diarrhea and hives.

These are the potential scenarios when a mast cell patient starts experiencing more severe symptoms than usual.

  1. The patient experiences flushing, nausea, diarrhea and hives. They don’t take rescue meds and the symptoms resolve. This is a mast cell reaction. This is not anaphylaxis.
  2. The patient experiences flushing, nausea, diarrhea and hives. They take rescue meds (not including epi here) and the symptoms resolve. This is a mast cell reaction. This is not anaphylaxis.
  3. The patient experiences flushing, nausea, diarrhea and hives. They may or may not take rescue meds (not including epi here). Either way, the symptoms do not resolve.   The amount of mast cell degranulation triggers a large scale reaction that initiates anaphylaxis. This is anaphylaxis and requires epinephrine. There are two possibilities here: it was anaphylaxis from the beginning, or it started as a mast cell reaction and became anaphylaxis. Either way, it requires epinephrine and other rescue meds.

It seems to me that when anaphylaxis occurs in mast cell patients as a sudden onset event that the symptoms seen are usually distinct from regular mast cell reaction symptoms. (This last sentence is based upon what I have experienced and what is reported to me by patients. There is no data on this.)


General notes on use of epinephrine

How do you know it is anaphylaxis? That’s the hard part. Mast cell experts feel differently about this. Most say to only use epi if you have trouble breathing or low blood pressure because then you know it is life threatening and thus anaphylaxis and not a mast cell reaction.

If you are having trouble breathing or low blood pressure (for adults, under 90 systolic), that is generally cited as the appropriate point to use epi. However, it is a conversation and decision that must be made with you and a doctor that knows you and your disease.

If you have had an episode before where you had severe symptoms and recovered without epinephrine, it is phenomenally unlikely that it was anaphylaxis.

If you think you may need epinephrine and are unsure, it is generally recommended to use your epipen. The reason for this is that epinephrine is pretty safe, despite how the movies depict it. The risk of using an epipen when you don’t need it is side effects of epinephrine use: rapid heartbeat, elevated blood pressure, anxiety, and generally not feeling great for a day or so. The risk of not using an epipen when you need it is death. People die from anaphylaxis with their epipens on them unused.



Meeting diagnostic criteria for anaphylaxis

As I reviewed in the previous post, there are many sets of diagnostic criteria for anaphylaxis. The one that is the most widely used in the WAO criteria published in 2006.  This set of criteria has been validated, meaning it was effective for correctly identifying patients experiencing anaphylaxis while excluding those who weren’t.  Even still, they note that about 5% of patients with anaphylaxis will not be covered by these criteria and to use discretion with this population.

The 2006 WAO criteria (shown below) are often used by emergency departments to determine whether or not epinephrine is needed. If the patient meets the criteria, epi is warranted.  This is one of the reasons why anaphylaxis is often considered synonymous with requirement of epinephrine.


2006 WAO Anaphylaxis Criteria
2006 WAO Anaphylaxis Criteria

Determining whether or not you have anaphylaxis when your blood pressure is not very low and you can breathe fine is not straightforward for mast cell patients. There are several charts that are often posted in mast cell groups that show four or five stages of anaphylaxis.  These charts are designed for people who do not have baseline allergic symptoms.  Mast cell patients have baseline allergic symptoms.

If you have mast cell disease and have flushing, nausea and hives regularly, that is not grade II anaphylaxis. That is mast cell disease.  Symptoms that are part of your normal baseline or reaction profile do not contribute to the overall assessment of anaphylaxis.  So let’s assume I have flushing, nausea and hives every day.  But then one day I also have diarrhea and tachycardia, which isn’t normal for me.  That is grade III anaphylaxis per the Ring and Messmer scale (shown below).  Whether or not you use epi at that point, assuming your blood pressure is not low and you can breathe okay, depends upon whether or not your doctor endorses the use of that scale.


Ring and Messmer Anaphylaxis Grading Scale
Ring and Messmer Anaphylaxis Grading Scale


Anaphylaxis vs anaphylactic shock

I often see people use anaphylaxis and anaphylactic shock interchangeably. They’re not the same thing.

Anaphylaxis is a severe, multisystem allergic reaction.

Shock is more properly called circulatory shock. It is a state arising from poor circulation such that tissues are not receiving sufficient blood supply.  Weak pulse, tachycardia, low heart rate, and mental status changes including loss of consciousness are all symptoms of shock.

Anaphylactic shock is circulatory shock caused by low blood pressure due to the vasodilation from large scale degranulation. By definition, it is blood pressure 30% below the patient’s baseline or below standard values (90 systolic for adults).  So if you aren’t experiencing circulatory shock, you aren’t having anaphylactic shock.



Sampson HA, et al. Second symposium on the definition and management of anaphylaxis: summary report – Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network symposium. J Allergy Clin Immunol 2006: 117(2), 391-397.

Brown, SGA. Clinical features and severity grading of anaphylaxis. Journal of Allergy and Clinical Immunology 2004: 114(2), 371-376.

Sampson HA, et al. Symposium on the definition and management of anaphylaxis: summary report. J Allergy Clin Immunol 2005; 115(3), 584-591.

Ring J, et al. History and classification of Anaphylaxis. Chem Immunol Allergy 2010: 95, 1-11.

The effects of cortisol on mast cells: Cortisol and HPA axis (Part 1 of 3)

Things I’m not great at: Knowing how many posts I need to cover all the effects cortisol has on mast cells.  So this is the first of three posts on cortisol and mast cells.  Then we will get back to the tables breaking down the effects of hormones on mast cells.
Cortisol is a glucocorticoid steroid hormone with far reaching anti-inflammatory actions. It is the product of a very complex endocrine system called the HPA axis.  HPA stands for hypothalamus-pituitary-adrenal.  The hypothalamus is in the brain and the pituitary is a small structure on the edge of the hypothalamus.  The adrenal glands are above the kidneys.

The hypothalamus, pituitary and adrenal glands all release a number of hormones that affect many bodily functions. Briefly, the hypothalamus receives signals from the nervous system to make corticotropin releasing hormone (CRH).  CRH induces the pituitary to make adrenocorticotropin hormone (ACTH). ACTH induces the adrenal glands to make cortisol.

Cortisol is most well known as the stress hormone, although it has many other functions. It can be released as a response to inflammation or physical or emotional trauma.  In such instances, signals from the nervous system tell the hypothalamus that it needs to make CRH.  CRH triggers vasodilation and increased vascular permeability to allow immune cells move from the bloodstream to inflamed spaces in tissue.  CRH also triggers manufacture of ACTH, which then triggers manufacture of cortisol.

When cortisol levels are high in the adrenal gland, epinephrine can be made from norepinephrine. Cortisol is thought to regulate the enzyme that makes epinephrine at several steps in the process.  Epinephrine is also part of the stress response and participates in the fight-or-flight response.

The role for which glucocorticoids are most often prescribed is suppression of inflammation. Cortisol production is initiated very early in an inflammatory response. Cortisol counteracts vasodilation seen by many inflammatory mediators.  Cortisol also decreases vascular permeability so immune cells are not able to easily leave the bloodstream and move into tissues.  Cortisol also affects gene expression so that inflammatory products are not made as much and anti-inflammatory products are made more.  (This will be discussed in great detail when I cover how cortisol affects mast cells.)

A number of synthetic glucocorticoids, like prednisone and dexamethasone, have similar behaviors and functions. The medication hydrocortisone functions the most like cortisol in the body.  Synthetic glucocorticoids stay in the blood longer and are more bioavailable than cortisol.  The amount of cortisol produced by the body changes throughout the day in time with other functions.  Synthetic glucocorticoids cannot mimic these changes exactly and are thus inferior to cortisol.  Small changes in amount of glucocorticoid can have major effects.


Oppong E, et al. Molecular mechanisms of glucocorticoid action in mast cells. Molecular and Cellular Endocrinology 2013: 380, 119-126.

Varghese R, et al. Association among stress, hypocortisolism, systemic inflammation and disease severity in chronic urticaria. Ann Allergy Asthma Immunol 2016: 116, 344-348.

Zappia CD, et al. Effects of histamine H1 receptor signaling on glucocorticoid receptor activity. Role of canonical and non-canonical pathways. Scientific Reports 2015: 5.

Coutinho AE, Chapman KE. The anti-inflammatory and immunosuppressive effects of glucocorticoids, recent developments and mechanistic insights. Mol Cell Endocrinol 2011: 335(1), 2-13.

Epinephrine: Dosage and safety

How should epinephrine be used?

Epinephrine administered into the side of the thigh is the preferred route. 0.3mg (Epipen strength) – 0.5mg is recommended for adults. This can be repeated every 5-15 minutes as necessary. 16-35% of patients need a second dose of epinephrine to manage initial symptoms. Epipen Jr. contains 0.15mg epinephrine, which is usually recommended up to 66 lbs. Dosage for children is 0.01 mg/kg.

Aqueous epinephrine diluted 1:1000, 0.1-0.3ml in 10ml NS can be used intravenously over several minutes as needed. For potentially dying subjects, epinephrine diluted 1:1000, 0.1ml in 0.9ml of blood or normal saline (1:10000) intravenously. Give as necessary for response.

Aqueous epinephrine diluted 1:1000, 0.1-0.2mg, can be administered at reaction site (bee sting, etc.)


Statements on the use of epinephrine

Intramuscular adrenaline is the acknowledged first line therapy for anaphylaxis, in hospital and in the community, and should be given as soon as the condition is recognized. There are no absolute contraindications to administering adrenaline in children. Absolute indications for prescribing self-injectable adrenaline and prior cardiorespiratory reactions, exercise-induced anaphylaxis, idiopathic anaphylaxis and persistent asthma with food allergy. Relative indications include peanut or tree nut allergy, reactions to small quantities of a given food, food allergy in teenagers, and living far away from a medical facility.

Reference: Muraru A et al. Allergy 2007; 62:857-71.


Statement of the World Allergy Organization

The Committee strongly believes that epinephrine is current under-utilized and often dosed suboptimally to treat anaphylaxis, is under-prescribed for potential future self-administration, that most of the reasons proposed to withhold its clinical use are flawed, and that the therapeutic benefits of epinephrine exceed the risk when given in appropriate IM doses.

Reference: Kemp SF, Lockey RF, Simons FER, et al. Allergy 2008; 63:1061-1070.


Epinephrine may cause pharmacologic adverse effects such as anxiety, fear, restlessness, headache, dizziness, palpitations, pallor, tremor. Rarely, especially after overdose, it may lead to ventricular arrhythmias, angina, MI, pulmonary edema, sudden sharp increase in BP, intracranial hemorrhage. There is, however, no absolute contraindication to epinephrine use in anaphylaxis.

Reference: Simons FER. J Allergy Clinical Immunol 2004;113:837-44.

Biphasic anaphylaxis

Anaphylaxis has several described variants, including monophasic (one episode of symptoms), biphasic (a second episode after resolution of symptoms), late onset (occurring several hours after exposure to antigen) and protracted (in which symptoms took several hours to resolve despite treatment.) There have been multiple studies on the incidence of biphasic reactions which yielded differing results.

Stark and Sullivan described a 20% incidence of biphasic reactions in 25 patients. They found that patients experienced their second reaction 1-8 hours after the resolution of symptoms. Reactions were 2.8X more likely to be biphasic if the trigger was ingested or if the onset of symptoms was longer than 30 minutes after exposure. Laryngeal edema in the throat was also a risk factor. Severity of initial reaction or treatment administered did not correlate to whether or not the reaction was biphasic.

Douglas reported a 5.8% incidence rate of biphasic anaphylaxis. They found that higher doses of corticosteroids may have decreased the incidence of a second phase.

Lee and Greenes specifically investigated children. They found occurrence 1.3-28.4 hours after the resolution of initial symptoms. Most had wheezing and shortness of breath. Some had abdominal pain. Low blood pressure was rare. Importantly, they found that delay in administration of epinephrine was a predisposed patients to a second reaction. Patients who had only one reaction were administered epinephrine, on average, 48 minutes after exposure; those with two reactions, 190 minutes after. No other risk factors were identified.

18% of patients in the Brazil and MacNamara study were found to have biphasic anaphylaxis. Second phase occurred 4.5-29.5 hours later. They were unable to find clinical features that distinguished biphasic patients from uniphasic, but those with two phases did require more epinephrine to resolve initial symptoms.

Forest-Hay found that nine patients out of 91 had biphasic reactions. Eight of those had symptoms within six hours, a finding not seen in other studies.

A large study done by Smit on Hong Kong hospitals found a 5.3% incidence of biphasic reactions. They found that the time of treatment to onset of second phase averaged 7.6 hours. 12/15 biphasic patients had mild reactions. In particular, they found that biphasic reactors were less likely to have respiratory involvement (35% vs 77%.)

Ellis and Day found a 19.4% biphasic reaction rate. The second phase appeared 2-38 hours after the initial resolution. 40% of these patients had the second phase more than ten hours after the end of the first phase. The second phase could be milder than, similar to or more severe than the first. However, 40% had a lifethreatening second phase and 20% needed more treatment to resolve the second phase than the first. Biphasic patients had longer lasting initial reactions, were given less epinephrine and received less steroids. Late biphasic reactors (after 8 hours) took an average of 193 minutes to resolve their initial symptoms vs 112 minutes for uniphasic reactors. Importantly, no biphasic reaction was found in any patient who administered epinephrine and resolve symptoms within 30 minutes of onset. No biphasic if responded completed in less than 30 minutes. All patients received epi for treatment.

Delay in administration of epinephrine, inadequate dosing of epinephrine for first response, or need for large doses of epinephrine were found to suggest that biphasic anaphylaxis was more likely. Corticosteroid administration was not definitively found to prevent a second phase, but was generally considered to be beneficial. Previous cardiovascular history, older age, and use of beta blockers were risk factors for biphasic reactions. Oral ingestion of the trigger elevated the likelihood of a second stage, but it was also seen in parenteral and inhaled exposures. Hospital admission for 24 hours after resolution of symptoms is recommended.

Studies of mastocytosis patients have found that they are more likely to experience anaphylaxis, but true investigation of whether or not they are more likely to have biphasic reactions has been undertaken.



Tole, John and Phil Lieberman. Biphasic Anaphylaxis: Review of Incidence, Clinical Predictors, and Observation Recommendations. Immunol Allergy Clin N Am 27 (2007) 309-326.

Douglas DM, Sukenick E, Andrade WP, et al. Biphasic systemic anaphylaxis: an inpatient and outpatient study. J Allergy Clin Immunol 1994; 93:977–85.

Lee JM, Greenes DS. Biphasic anaphylactic reactions in pediatrics. Pediatrics 2000;106: 762–6.

Ellis AK, Day JH. Incidence and characteristics of biphasic anaphylaxis: a prospective evaluation of 103 patients. Ann Allergy Asthma Immunol 2007; 98(1):64–9.

Brazil E, MacNamara AF. ‘‘Not so immediate’’ hypersensitivity: the danger of biphasic anaphylactic reactions. J Accid Emerg Med 1998 ;15: 252–3.

Forrest-Hay A, Taylor C, Tolchard S. Biphasic anaphylaxis in aUKemergency department. Presented at Open Paper Presentations of the 2003 Scientific Symposium of the Resuscitation Council of the United Kingdom (abstract)

Smit DV, Cameron PA, Rainer TH. Anaphylaxis presentations to an emergency department in Hong Kong: incidence and predictors of biphasic reactions. J Emerg Med 2005;28(4): 381–8.

Beautiful things I can’t have

I’m a Buffy fan girl.  I’m sure this surprises no one.  Strong characters, the supernatural and witty banter is basically a recipe to get me as a loyal fan.  I know all the words to the sing along episode and have been compared to Willow more times than I can count. 

There’s an episode in the fifth season where Xander and Anya go to look at an apartment.  She is upset because she doesn’t think they’ll get it.  Xander asks her what’s wrong and she says this:
“What’s going on with me is that my arm hurts… and I’m tired… and I don’t really feel like taking a tour of beautiful things I can’t have.” 
That’s how I feel right now.  I don’t really feel like looking at beautiful things I can’t have.
I have always identified as a traveler.  As a kid, I would take out language books from the library with the clear intention of learning the language for when I went there.  When I was 19, it occurred to me that if I saved up my money, I could go wherever I wanted.  I got some books and planned a trip and went to Europe. 
In 2007, when I was starting to get sick, I went backpacking in Scandinavia.  I went hiking and got really lost in this beautiful national park in Norway.  I got drunk on a ferry sailing between Estonia and Finland.  I felt tired and at the end, I felt sick, but I was mostly able to do everything I wanted to do.
In 2009, I bought tickets to Ireland and went for a quick four day trip with my boyfriend at the time.  I was exhausted and sick, but I was still able to go.  I needed a lot of sleep but otherwise it was fine.
I took a bunch of other trips.  In 2012, I went to Seattle and we all know how that went.  I came home to lots of serious news and slowly I stopped thinking of myself as a traveler because it hurt a lot.  I stopped reading my dozens of travel books and drawing maps and studying languages.  Doing those things felt like sticking my hand into an open wound.  It felt like trying to push through the looking glass only to find I was still in this strange facsimile of my life where I was sick and couldn’t do this thing that defined me.
In the last couple of weeks, I started feeling like maybe this was going to be possible again.  Maybe I could travel, if I had someone with me to help me.  Maybe I could plan trips again and look forward to them.  Maybe I could go to all these faraway places and feel this stillness in my soul that I only find when I’m away from home. 
I was supposed to go to Asia in the fall.  I was originally supposed to go in the spring but I was too sick.  So we decided to go in the fall.  We were going to fly through Dubai to Bangkok, spend a few days in Bangkok, take a private tour to Angkor Wat in Cambodia, go to an elephant preserve, spend a few days in Dubai on the way back.  I have been planning this for months, both the fun part and the not insignificant logistical shuffle of travelling out of the country with a ton of medication, medical supplies and large bags of IV solutions.  I was planning to book our airfare tomorrow.
But a few days ago I found that one of my best friends was stealing from me, and she was supposed to go to Asia with me.  She was supposed to help me to live this dream that has buried for years under the rubble of mast cell disease. 
I’m more upset about Asia than I am about the money.  Because I found out a couple of weeks ago that I could still travel, but only if I’m with someone who loves me and understands my disease and what to do in an emergency.  I cannot travel alone.  I wish I could, but I can’t deny that it’s too dangerous for me. 
The fallout of this woman stealing from me has been significant.  I have needed epinephrine and lots of IV meds and steroids, and even now as I type this, my skin is burning and my heart is racing and my insides are doing that cringe and shudder that means that with just a little push, I can be in trouble again.
When you have mast cell disease and people mistreat you, your choices are to move on quickly so as not to anaphylax or to get mad and risk ending up in the hospital.
It’s not as much of a choice as you might think.
If I fall down and scrape my leg, it is an emergency.
If I forget to take a single dose of any of my many medications, it is an emergency.
If I forget to put on the AC and fall asleep, it is an emergency.
If I get too mad, it is an emergency.
Around 4 this afternoon, I locked a syringe of 50 mg IV Benadryl into my PICC line and angrily uncapped my Epipen.  “I really hate that I’m so sick that I have to use epinephrine at home on a regular basis.  That makes me really mad,” I told my mother as I brought the tip down against the outside of my thigh.
There seems to be some confusion over whether or not what my “friend” did was wrong because she “tried to pay it.”  (I know, don’t get me started.)  So let me make it really clear.
I don’t care about the money.  If she had asked, I would have given it to her.  This is not about the money.
This is about everything else she took from me.
She took my right to feel like I can trust people to take care of me.
She took my right to feel like I can accept help without getting screwed.
She took a lot of my energy over the course of our friendship.  A lot. 
She took my safety because this was such a violation that I can’t help but feel angry and it is making living in this body even more dangerous than usual.
She took my ability to go on this trip.  She took my ability to feel like I can get this part of myself back. 
So disappointing.  I have never been more disappointed in a person in my entire life. 
And for the sake of being thorough, I want to deal with this: at least one person thinks that it’s okay that they knew about it and didn’t tell me because she wasn’t “being malicious.” (I don’t even know what that means.)
What she did is criminal.  Stealing is a crime.  Stealing from a very sick person is a more serious crime.  This is not the personal opinion of Lisa Klimas.  This is the opinion of the criminal code of the State of Massachusetts.  If you know someone is preying upon an ill person, and you do nothing, you are just as guilty.  You are not a “good person” who is getting “blamed by association.”  You are a loser.    
My friends are closing ranks around me.  I have received over a dozen offers to do my food shopping, all with the added promise that they will not steal from me.  They are making me laugh.  (Quote of the day:  “’How does one pay a credit card without the bill?’ ‘Oh, I just write credit card on cash and throw it out the window, does that not work?’”) They are reassuring me that they will not betray me.  They are reassuring me that they will take care of me and that they love me.   They are letting me know that they will support me however this plays out.
They are really angry that this happened to me.  Honestly, I am a little surprised at how angry they are.  But I get it.
I’m tired of looking at beautiful things that I can’t have. 
And they’re tired of watching me. 
So disappointing.