I wouldn’t be writing again if I weren’t so confused about what’s happening to me right now.
In a previous thread, I described an episode where I increased my thyroid hormones: from taking 50 mcg of T4 daily (for about 3 weeks) to introducing 19 mcg of T3 within 24 hours. I took 1/4 of the pill at night, then another 1/4 with my 50 mcg T4 in the morning, and another 1/4 at 15:00 the same day.
Initially, I felt great, but by 21:00, symptoms escalated rapidly—numb, cold hands and feet, almost fainting, and inability to hold my phone. I'm unsure if this was a hyper or hypo crash, my body was asking for more T3 or rejecting it?
For two days after the episode, I cut back to 50 mcg of T4 only, but numbness in my hands and feet continued, along with intense anxiety, disorientation, weird vision (not double, but delayed processing), light/sound sensitivity, and overwhelming sensations that made me feel like I was on the verge of collapse.
On the third day, I stopped all thyroid hormones due to increased anxiety, tinnitus (especially at night), frequent bowel movements, lightheadedness, and air hunger—these felt like hyper symptoms, except for the numb extremities, which I had never experienced before.
Here are my blood tests:
Day 4 14:00 fasting (last 50 T4 was taking on Day 3 ~7 am, ):
TSH: 2.66 (Range: 0.35–4.94)
FT4: 13.8 (Range: 9.0–19.1) 48%
(No FT3 taken)
Day 5 15:00 (off all thyroid meds for 2 days):
TSH: 3.01 (Range: 0.35–4.94)
FT4: 13.0 (Range: 9.0–19.1) 40%
FT3: 3.8 (Range: 2.4–6.0) 39%
I’m now on day 6, still dealing with severe anxiety, dizziness, and light/sound sensitivity. I haven’t taken any hormones since Monday, and while I fear my TSH is rising, I’m also scared that resuming T4 (50 mcg) might make things worse.
Question to try to help me understand what happened..
Can a single day of T3 introduction cause such a hyper state, even if the labs don’t show it? Or was it the withdrawal of T3 that caused this whole shock, like my body is trying to ask for more? I have never been so sensitive to T3 before but the only thing which changed prior to all these symptoms manifesting was the introduction of T3. Back in Poland I used to take Novothyral 50T4+10T3 tabs daily, but with moving to UK the endocrinologist here has put me on 50 T4. I want to introduce T3 again but after this episode am very unsure and scared on how to proceed. I still have some Novothyral left with me as well as Tiromel T3.
I’m really struggling to understand what’s happening and would appreciate any advice or similar experiences.
Thank you.
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anakondratenko
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Why are you taking T3 when your T4 dose is only 50mcg which is basically just a starter dose?
You have to be on a steady dose of hormone for at least 6 weeks before testing to allow the dose to settle in the body and so give a reliable reading
Suggest you start again on 50mcg, hold that dose for 6 weeks then test again by which time you will need to increase to 75mcg ....again wait for 6 weeks and test. Those results will indicate how you need to procede
There is no quick fix, like taking paracetamol for a headache....finding your therapeutic dose is a long slow process
Adding 19mcg T3 quickly was very likely responsible for the symptoms....a bit like putting high octane racing fuel in an old car!!
Your TSH will rise if your hormone level is low.
Where did you get the advice to add thyroid hormone as you have done because it is wrong! Your body has become confused by the rapid dose changes
Your results above are meaningless I'm afraid, the dosing and testing protocols are wrong....did you do them privately?
We don't usually introduce T3 until it is clear that T4 to T3 conversion in the body ( eg in liver and kidneys) is impaired....that is when the T4 you are taking results in high FT4 with low FT3.
The latest bloodwork (21st of August before starting with 50 T4 and after 2 weeks of taking no meds):
TSH 12.10 Range: 0.27-4.2
FT4 12.4 Range: 12-22 4%
FT3 4.2 Range: 3.1-6.8 30%
These results indicate a serious lack of T4...not poor conversion. The high TSH is the pituitary's message to the thyroid gland to produce more hormone.....or to you to add replacement hormone as T4!
Your UK endo will have started you on 50mcg with the intention of gradually increasing the dose ( as described above) Were you asked to go back after 6/8 weeks on 50mcg.....if not you should have been.
However, your GP should be able to treat you like this....make an appointment with them. You are very unlikely to be prescribed T3 at this early stage, if at all.
Sorry you have had this experience, a knowledgeable doctor should be able to correct your dose.
DippyDame thank you so much for taking your time to respond. I've been diagnosed with Hashimoto's and subclinical hypothyroidism since 2018, have moved to combi-therapy with T3/T4 in 2020 or so and have been worry-free up until June 2024 when the first episode of overmedication happened and caused a similar flare up (worse insomnia, high anxiety but no numbness back then). My usual dose this whole time since 2020 was 50T4 and 10T3 (a half of Novothyral 100/20 tablet, taken in the morning). However since the start of this year I've been particularly good about sticking to the gluten free dairy free sugar free diet, taking supplements (selenium, D, B, betaine etc.) and have seen that my ATPO antibodies which have been up always increasing for as long as I can remember (1100 in October 2023) started to go down and were the lowest in in July 2024 - 332, I haven't had this low of a number since 2019. My theory and I have no idea if it's valid or not is that maybe as the immune attack has decreased, my thyroid started to produce more of the hormone and that's why I can't tolerate any more the previous doses? The blood tests I've added above were done 1. in the hospital on Monday 2. in the emergency on Tuesday.. The regime is awkward just because of the intensity of the symptoms and me trying to get any sort of reading to see where I'm at.
Thank you for you advice, I will try to go back to 50 mcg dose and stay on it for enough time to understand my new situation with conversion and will know for the future to never be so quick again.. to be honest my audacity with dose increase came from never having any problems with T3 before.. I even remember sometimes running out of T4 just taking T3 only on some days and feeling fine. Bad assumption clearly as I guess with Hashimoto the situation is always changing. Thank you once again.
DippyDame oh, and yes! my UK endocrinologist did ask me to go back to an appointment with him after 6 weeks on a 50 T4 dose.. but now I guess having messed everything up, I should postpone the visit once I have new 6 weeks passed taking 50 T4 only with no improvisations or disruptions..
I have a very involved thyroid condition so I understand how complex it can all be
Hashi symptoms and hormone levels will occasionally fluctuate as the thyroid gland atrophies and hormones are dumped in the system causing transitory (very) high free hormone levels which will eventually fall back after the attack.
Your perceived hormone intolerance could be the body causing symptoms which indicate it is asking for/ needs more hormone.
It's important to listen to your body as an old medic friend once kept repeating!
Undermedication can sometimes feel like overmedication, and vice versa , which can confuse the issue!
You haven't "messed everything up".....you've just hit a bump in the road. It can be sorted!
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