Reducing T3 to increase TSH

[rubyred]

Please can I ask after a reduction in T3 how long does it take the TSH to react to the change.

Thank you 😊

[greygoose]

How long is a piece of string? Everything thyroid is unpredictable. But, why on earth do you want to increase your TSH?

[rubyred in reply to greygoose]

Hi thanks for reply. I’ve had 2 emergency admissions to hospital. I have atrial fibrillation diagnosed 1st visit then second trip found cardiomyopathy. I’m waiting for cardioversion. The cardiology team are keen to work with the endocrine who is concerned about my TSH which has always been suppressed since starting T3. I’ve agreed down titration from 60 to 40 prior to treatment as because of AF they are concerned if I was slightly over may have increased heart rate. I’m now down to 40 T3 but have brain fog and fatigue. I’m on a reduced fluid intake of between 1.5 to 2 litres per day. Since the final T3 drop I’ve had to reduce my fluid intake to stop me coughing. The cardiologist had wanted the cardioversion in 6 weeks but I’m told by waiting list they don’t have that capacity. I’m due to have blood test mid January. Sorry lots of info on there but I hope gives a clear picture why reducing xx

[greygoose in reply to rubyred]

So, what was your FT3 level on 60 mcg T3?

[rubyred in reply to greygoose]

Hi levels taken mid November

T4 = -5.4 (7.5-21)

T3 = 8.8 (3.8-6)

TSH = -0.01 (0.35-3.5)

T3 was taken 9 hours earlier. Endocrine not bothered by the T3 level as is open to and prescribes T3 on NHS. She is fully aware that T3 peaks in body depending when dose last taken.

[greygoose in reply to rubyred]

Well, 9 hours should have been fine. But, if she prescribes T3, she should also know that TSH is going to be very low/suppressed when you take it. And that's for a very good reason: you don't need it anymore. And, you don't need to raise is. Your heart probelms are nothing to do with your TSH. Far more likely to be due to the over-range FT3. I'm afraid she's got this all upside-down and inside-out! She should be dosing by the FT3, not the TSH.

[rubyred in reply to greygoose]

I take my T3 split across the day. Last dose at bed time so will always be around the same level.

[greygoose in reply to rubyred]

Not if you reduce your dose it won't.

[shaws Administrator in reply to rubyred]

I take T3 once daily. Therefore taking thyroid hormone repalcements don't interfere wih my normal life.

[Zazbag]

I'm self-medicating with 22.5mcg of T3. The NHS endo I saw recently wanted me to reduce the dose to 17.5mcg, he calculated that this would put my TSH back into the normal range. He said I should have my bloods tested 6 weeks after the dose reduction, so my guess is that it is thought to take 6 weeks for the change to affect TSH. However, T3 is a very fast-acting hormone, so I'm not sure whether it really does take 6 weeks, it's just my guess based on what this NHS endo said.

FYI I haven't listened to him because I feel great on 22.5mcg, all my hypo symptoms have resolved, and T3 is expected to suppress TSH so I was expecting it to become very low anyway.

[shaws Administrator in reply to Zazbag]

We don't want 'normal range'. We need a TSH of 1 or lower.

[Zazbag in reply to shaws]

My TSH is suppressed, I mean "normal" as in more than 0.27.

[shaws Administrator in reply to Zazbag]

I really don't bother with TSH as I'm more concerned about how 'I feel'. When I feel well, with no clinical symptoms, that's the dose I stay on.

TSH is important if we have symptoms and we're unaware we have a dysfunctional thyroid gland.

[Zazbag in reply to shaws]

I'm not sure why you're saying this, I didn't say I was trying to increase my TSH, I said my NHS endo wanted me to and I didn't listen to him anyway because I feel good on my current dose. I just explained the context to answer the OP's question about how long it takes for TSH to increase when you change your dose of T3.

[rubyred in reply to shaws]

I have only agreed to make sure it’s not contribute to my fluctuation heart rates. I will make it very clear I’m under active but equally want to have my heart back into a normal rhythm and confirmation that the heart failure is caused by the atrial fibrillation. Then I will expect the T3 to be raised back up but with ECGs and other testing to make sure all stays well. Xx

[shaws Administrator in reply to rubyred]

When I was quite newly diagnosed levo gave me awful palpitations mostly in the middle of the night and the cardiologist was puzzled and was considering putting an implant into my heart 'to see what was going;.

Co-incidentally the Endocrinologist added some T3 to my T4 dose, and all my symptoms disappeared.

I did not need an implant and heart was calm.

I also understand what it's like to have severe palps.

[rubyred in reply to shaws]

I was also unwell on levo but never had palpitations. Have been getting more unwell and more breathless over a period of time. Atrial fibrillation was the cause but at no point have I ever experienced palpitations. When I was admitted the first time my BPM were 177. Never felt any thing other than panting to breathe. Even hooked up to machines once my heart was lower at 120 BPM I still felt nothing. After 2nd admission I’m now on 6 different meds to lower heart rate and now at 60 BPM. TBF some of those meds may also be contributing to the fatigue. X