I broke my collarbone so the following is not really a transcript but my notes on the listener question. It has been challenging to type so I took some notes instead of typing up a transcript.

Listener question:

I recently discovered your podcast and have power listened to every single episode since the weekend before last. Thank you so much for all you’re doing; you’ve already helped so much.

My question is pertaining to the correlation between Hashimoto and Urticaria. I’ve suffered with chronic hives for a few years; however, must admit, I haven’t been as proactive as I should have been to find resolve. I am changing that.

My hives come and go. Approximately 3-4 episodes a year, each about 3-4 weeks in duration. There are no apparent triggers with diet, activity level or stress. My endocrinologist pulled my off Synthroid and onto Tirosint. I was hive free for quite sometime following the change a I was assuming it was secondary the Synthroid.

Wrong! Sadly, they’re back and I have already scheduled to see my Endocrinologist but also was curious as to your thoughts.

Thank you again,
Susan

Everything I have read about thyroid and hives says there is no real explanation for why it happens in thyroid patients but I have some ideas. 

Hives or urticaria are a reaction by your immune system that causes the release of histamine and results in swelling, itching and redness of the skin. 

A mast cell is a cell full of white blood cells called basophils and are found in connective tissues. They release histamine and other chemicals during an inflammatory or allergic reaction. 

Histamine is a chemical that our cells release in response to an injury or in allergic reactions or inflammation. it causes your smooth muscle tissue to contract and capillaries to dilate or swell up so white blood cells can get to the source of the problem and attack. It plays a big role in controlling itchiness in the body. 

It is a neurotransmitter that also plays a role in digestion as a part of stomach acid so you can break food down properly and the central nervous system uses it to communicate between brain and body. 

Hives are the result of histamine which can be caused by consuming foods high in histamine, small intestinal bacterial overgrowth, intestinal permeability, and a deficiency in an enzyme called diamine oxidase (helps clear histamine from the body). 

In about half of patients with chronic idiopathic hives, the explanation is that body's immune system is, in a sense, overactive. The urticaria is "autoimmune". The immune system is attacking the normal tissues of the body and causing hives as a result.

https://www.ncbi.nlm.nih.gov/pubmed/19331714

Caused by an allergic reaction to medications and food.

Hives lasting less than six weeks: The most common causes are certain foods, medications, or infections. Insect bites and internal disease may also be responsible. 

The most common foods that cause hives are nuts, chocolate, fish, tomatoes, eggs, fresh berries, and milk.

Foods high in histamine include things like: 

• fermented foods and drinks including alcohol

• vinegar based foods

• cured meats including bacon

• dried fruits

• citrus

• cheese that is aged

• nuts

• avocados, eggplant, spinach, tomatoes

• smoked fish and certain kinds of fish

Foods that keep the Diamine oxidase enzyme from working: 

• alcohol

• energy drinks

• black, mate and green teas

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5839887/ —- a histamine free diet is helpful for tx of adult patients with chronic spontaneous urticaria

Another option for urticaria is adrenal dysfucntion. 

When the body experiences stress it can cause a flare of hives due to increased adrenocorticotrophic hormone or ACTH. ACTH is secreted by the pituitary gland which then stimulates the adrenal gland to release cortisol. 

This can be triggered by emotional or physical stress in the body. Keep in mind that the physical stress can be inflammation from food intolerances or unmanaged autoimmune disease. 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3256343/

https://www.ncbi.nlm.nih.gov/pubmed/11270265 (A cross-linking of IgE receptors of mastocytes induced by antithyroid antibodies may be a cause of histamine release)

IgE or immunoglobulin E are antibodies made by the immune system when you have an allergy to something which will cause an allergic reaction to something from the environment or from a food.

chronic infections or autoimmune disease can cause that overreaction in your immune system.