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Thyroid Patients Share What Triggers Their Flare Ups

Thyroid Patients Share What Triggers Their Flare Ups

Flare ups seems to be rather common among those with a thyroid condition. They are defined as an increase in symptoms of the thyroid condition. A thyroid flare up usually lasts from a day to a week or so. Mine usually last one to two days.

Some people call an increase in thyroid antibody levels (after having them low for quite some time) a flare up. And others also use the term to describe a change in thyroid levels. I tend not to. I think this is confusing!

Symptoms can differ from person to person, although the most commonly reported in a flare up are:

  • Increased fatigue
  • Heaviness (as if your body is being weighed down)
  • Worsened mental health
  • Brain fog
  • Migraines
  • Flu-like symptoms (aches and pains)
  • Switching between feeling really cold and really hot

Common triggers are said to be alcohol, poor food choices, mental or physical overexertion, stress, poor sleep, viral/bacterial or fungal infections, pregnancy and menstruation. However, as with everything, there is no set of rules for a thyroid flare up.

Over time, I have got better at knowing what triggers my thyroid flare ups, so that I can avoid them and reduce the number greatly. However, sometimes I’m still surprised and caught off guard as I discover an unlikely trigger. Read more about preventing, overcoming and coping with thyroid flare ups here.

So, I asked the thyroid community:

What has been the most unexpected cause of a thyroid flare up for you?

Thyroid Patients Share What Triggers Their Flare Ups

“This week my pollen allergies turned into a sinus infection/illness which then wiped me out for 3 days. Couldn’t get off the couch. Zero energy. I had to get a Myers cocktail/vitamin drip to finally get some energy back. Also steroids.”

“For me it’s pretty much every day that I get up really early, and go around without a nap or little rest, it drains me before 5pm usually. It used to be so frustrating but now that I kind of get how I work, I’ve been able to manage it better.”

“Getting a tattoo.”

Thyroid Patients Share What Triggers Their Flare Ups

“Mine is stress. I’m really struggling this week.”

“Started with hives, which is new for me.”

“High blood pressure. I stopped taking my Synthroid (thyroid medication) and that’s what happened. I’m back on it again.”


“Wearing heels!”

Thyroid Patients Share What Triggers Their Flare Ups
“Just cooking a big family meal on a Sunday can take me down for two or three days after! Which sucks because cooking is my zen therapy usually!”
“It’s usually diet related. Bread messes me up. And sugar. Combine the two with stress and I’m a hot mess.”
“A new one for me is travelling. Wipes me out for days.”
Thyroid Patients Share What Triggers Their Flare Ups
“Travelling that involves multiple forms of transport; weeks where my work week has two or more socialising/hosting things in it or a run of four consecutive weeks with jam packed weekends (as well as week night social things) and no down time other than for chores.”
“Busy at work, insufficient fluids, stress. Had a tooth out two weeks ago and pain was horrific – wiped me out completely for four days!”
Thyroid Patients Share What Triggers Their Flare Ups
“I had one alcoholic (a single measure! ) drink and it wiped me out for days. I thought I’d be OK. Boy was I wrong! Back to no alcohol it is.”
“Lack of sleep. working out too many days in a row.”
“Fighting against/ignoring the disease. I think I’m being strong, but I make it worse.”
Thyroid Patients Share What Triggers Their Flare Ups
“Sunlight and heat are big triggers for me.”
“When my brother passed last year unexpectedly.”
“Drinking coffee!”
“Driving more than 30mins. makes me so exhausted and feels like I wanna collapse.”
Thyroid Patients Share What Triggers Their Flare Ups
“I’m only a few months in to a new role and felt like I was finding my feet doing presentations and training again but boy did I feel it! An exhaustion like no other!!! Just another reminder I need to pace myself and understand my limitations.”
Thyroid Patients Share What Triggers Their Flare Ups

Add your own in the comments section below. 

Read other blogs in the ‘Thyroid Patients Explain’ format here

Related post: Thyroid Patients Explain How Their Flare Ups Feel

If you are on thyroid medication and experiencing on going issues and symptoms, it could mean that you are not optimally treated, or have other problems you still need addressing.

Please know that you are certainly not alone and many patients do get better with optimal treatment. A properly treated thyroid condition should have no or very few symptoms. Of course, other illness, conditions and deficiencies can cause problems too, so explore them all if possible. Please see some ideas on where to start, here.

You can click on the hyperlinks in the above post to learn more and see references to information given.

About Author

Rachel Hill is the highly ranked and multi-award winning thyroid patient advocate, writer, speaker and author behind The Invisible Hypothyroidism. Her thyroid advocacy work includes writing articles, authoring books, producing her Thyroid Family email newsletters and speaking on podcasts and at events about the many aspects thyroid disease affects and how to overcome these. She is well-recognised as a crucial and influential contributor to the thyroid community and has a large social media presence. Her bestselling books include "Be Your Own Thyroid Advocate" and "You, Me and Hypothyroidism".


  • Jane
    February 9, 2022 at 10:19 pm

    Alcohol and artificial sweeteners are definite triggers for me. Also acacia, aka gum Arabic. Used as a filler in some brands of medication, including some thyroid meds! Have to check the ingredients on everything, for acacia in paracetamol, sweeteners in cough medicine etc. So many soft drinks now have sweeteners in them, and I used to suck mints to keep me going until I realised they contain acacia.

  • Anita
    August 14, 2020 at 9:40 am

    Sometimes I am feeling ok and other times completely wiped out. Does anyone know if having underactive thyroid is different MEN vs. WOMEN? My husband also has underactive thyroid and some days he’s so active and other days purely wiped out. When we are both feeling good/fine, we tackle alot of work around the house together. I don’t sleep well, as a woman, sleep for 5 hrs. then up for an hour, then go back to bed and sleep some more. I don’t like it at all. I am considering going to an endocrine doctor very soon. I have been on levothyroxine for about 4 yrs. now – recently took the Euthyrox brand, and that makes me feel even worse. Asking my pharmacist to put me back on levothyroxine or Synthroid brand, I did better with them. Thanks for doing this for us Rachel who have to suffer with this terrible disease.

  • Caz / InvisiblyMe
    December 4, 2019 at 11:03 am

    Oooo these are really interesting! It’s fascinating how it’s so different for everyone in terms of what causes a flare up of different symptoms for different conditions. The tattoo one made me wonder whether many people have found that, and how it works. I saw another blogger write about MS with getting a tattoo and she has her done without any problems; I’ve wanted one for years but now I’m a little concerned as to how my body would respond to it. Really interesting ones here! xx

  • Bunga Noura
    December 4, 2019 at 5:37 am

    It’s been 5 years since my Hashimoto’s and thyroid cancer diagnosis. I notice that my flare-ups were mostly triggered by :
    1. Stress at workplace
    2. Lack of sleep
    3. Consuming gluten, sugar, and processed foods

  • Eri
    December 3, 2019 at 8:57 am

    I am just learning my triggers as the whole Hashimoto’s world is new to me. I learned quite a lot about myself so far- lack of sleep is the number one, makes me really irritated and exhausted. Then some smells and noises, to much exercise, alcohol, sugar (and I love it so much), travelling/long driving and social events with unknown people and/or in unknown places. I noticed that also taking the airplane makes me feel really bad while I am on, having headaches and nausea because of the smell and afterwards it takes me days to come back to my ‘normal’.


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