Stopped T3 before blood tests. Doctor now sayin... - Thyroid UK

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Stopped T3 before blood tests. Doctor now saying result inaccurate.

lucylocks profile image
14 Replies

Hi

I posted recently about my daughter who is self medicating with T3. She had been suffering hypo. symptoms for years but G.P. would not treat as her TSH was in range. Every time she had it tested it was creeping up until eventually it was 4.7 and top of range. is 4.7. and she would still not treat.

Years ago she decided to see Dr. Skinner and he diagnosed her hypo. She took up to 175mcg. levo. but did not feel any better. She then tried Thyroid-S and again did not find much improvement so eventually started to self treat with T3. She takes 100mcg. daily with no over medicated symptoms.

She recently went to the Doctor about another problem and the Doctor said she wanted check her thyroid as she saw on the screen she was borderline last time she had it checked. At this point my daughter had not said she was taking T3 so decided to stop it to have the blood test. She stopped the T3 for 16 days before the test.

The Doctor rang and said she was now hypo. as her TSH is now 32 and offered her levo. It was at this point my daughter told her she had been self treating with T3 and wanted to take this as she had tried levo. before and it did not suit her. Doctor said T3 would weaken the heart and bones but after trying to dissuade her to take it eventually said, it was up to my daughter if she wanted to take it.

She has now been back to the Doctor and she is now saying she is NOT hypo. because the TSH will be flawed as she needed to be off the T3 for six weeks to get an accurate result. My daughter said six weeks is for levo. NOT T3 as T3 gets out of your system much quicker, No the Doctor said it is six weeks for all thyroid meds. and is still insisting the result will be flawed so has now gone from having a hypo. diagnoses to not having one.

Can anyone please point me to any research papers or information on how long T3 does actually take get out of the blood to give an accurate result.

Any thoughts and advice is gratefully appreciated.

Many thanks.

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lucylocks
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14 Replies
Clutter profile image
Clutter

Lucylocks,

ThyCa patients are taken off Levothyroxine 4 weeks prior to RAI to allow TSH to rise >30. For two of those weeks I was prescribed T3, so 2 weeks off T3 my TSH was >30. There should be next to no T3 in anyone's system 3.5 - 4 days after last T3 dose.

It would appear that your daughter has very little natural thyroid function to have TSH 32 16 days after stopping T3. TSH 32 means your daughter is overtly hypothyroid and her GP should prescribe Levothyroxine or T3 now. It doesn't make sense to wait for TSH to climb even higher.

lucylocks profile image
lucylocks in reply to Clutter

Thank you Clutter, do you have a view on jimh111's reply below ? (second paragraph)

jimh111 profile image
jimh111

The elimination half-live of triiodothyronine (T3) is about 24 hours in adults. Liothyronine (L-T3 the tablet form) has a half life of up to 48 according to some manufacturers. Whichever figure you take less than 2% of the T3 will be in her blood after two weeks. I don't think there are papers on this as such, it's just simple arithmetic. Her very high dose of L-T3 is likely to have down-regulated her hypothalamic pituitary thyroid axis which in plain English means her TSH is coming out lower than it would do if she had never taken L-T3. So the TSH figure of 32 might be an underestimate if anything.

However, her TSH has risen and it will take about six weeks for her fT4 level to build up. After this she might have normal fT3, fT4 and TSH levels. So on reflection I guess the doctor is right, from a blood test point of view you have to wait until things have settled back to normal.

These comments refer to getting an accurate assessment of how her thyroid is performing. It may be that she has good hormone levels but is hypothyroid, you must pay attention to symptoms and response to medication.

lucylocks profile image
lucylocks in reply to jimh111

Thank you jimh111.

your reply is interesting, especially second paragraph. She has now gone back on T3 but I am now wondering if she had stayed off it for six weeks her levels would look different.

humanbean profile image
humanbean

If your daughter has been treating herself for hypothyroidism, she is under no obligation to have thyroid function tests from her doctor.

Doctors can recommend and suggest but, unless someone has been sectioned, doctors can't force patients to be tested, or take any medication, or undergo any examination, or anything else.

I was put on Levo in 2013 and it made me feel so awful I wasn't prepared to stay on it long. I bought my own thyroid meds from then on and have told my doctor I'll manage my own thyroid and pay for my own thyroid function tests. She asked me why I was doing this and I said (politely) that I thought NHS guidelines for the treatment of hypothyroidism were sadistic and inadequate. She looked startled but hasn't mentioned my thyroid since. It is not an issue between us.

Similarly, I have high cholesterol and have been offered statins twice. I refused both times and my doctor has never suggested testing my cholesterol since. If I won't take the official treatment then what is the point?

Unfortunately, your daughter has left herself open to being bullied. If your daughter makes it clear that she takes responsibility for her own thyroid, in both meds and testing, then hopefully the doctor won't be able to continue bullying her.

humanbean profile image
humanbean in reply to humanbean

I should add, just for completeness ...

If someone is receiving treatment from the NHS and they refuse to be tested or examined to see if the treatment is working as expected, then the NHS would almost certainly refuse to supply the treatment any more.

So, refusing to co-operate with tests and examinations when being treated by a doctor/NHS will have consequences.

lucylocks profile image
lucylocks in reply to humanbean

Thank you humanbean.

She really wanted an official diagnoses of hypothyroidism that is why she agreed to the test.

humanbean profile image
humanbean in reply to lucylocks

Well, she should have one now. A TSH of 32 can't be achieved (as far as I know) by anyone who isn't hypothyroid.

lucylocks profile image
lucylocks in reply to humanbean

What do you think of jimh111 reply? (second paragraph)

humanbean profile image
humanbean in reply to lucylocks

Sorry, I don't feel competent to comment on the science. I don't know what would happen if your daughter managed to stay off meds completely for 6 weeks.

Just a personal anecdote :

I took high doses of T3-only (about 150mcg per day by the end, but briefly went up to 200mcg per day) for a couple of months about 3 years ago. I did this to reduce extremely high reverse T3. I had never had very high TSH - it went up to a maximum of about 6, but my Free T3 and Free T4 were bottom of the reference range.

I came off those high doses of T3 and spent about three months untreated. My TSH was about 4 after those high doses of T3 followed by three months untreated. Since that time I've taken either NDT or T3-only, and I don't have a clue what my untreated levels would now be.

There is no doubt in my mind that high dose T3 will change the way the hypothalamus-pituitary-thyroid axis works, possibly for ever, and the changes might actually make it harder to get a diagnosis. But I'm afraid I don't know the science behind it.

lucylocks profile image
lucylocks in reply to humanbean

It is all very complicated isn't it.

We do think though my daughter has thyroid hormone resistance as high doses of T3 are the only meds. that have helped her. She did get up to 200mcg. like you at one time and it was only at this dose she got over medication symptoms, when she reduced to 175mcg. the symptoms stopped.

She was taking 100mcg. before stopping for the blood test, now back up to 75mcg. but not feeling too good, just hoping she improves soon.

jimh111 profile image
jimh111

Just a few comments. When diagnosed she had a marginally elevated TSH and did not respond to 175 mcg levothyroxine. Thus her symptoms would not be due to a failing thyroid gland. She feels better on 100 mcg liothyronine which is a large dose, about double what a patient without a thyroid would need. This suggests she has some form of resistance to thyroid hormone.

She could now also have a failing thyroid but she would have to come off thyroid hormone for six weeks to verify this. If this were the case her doctor would medicate her for primary hypothyroidism. This wouldn't be much use as she has already tried a large dose of levothyroxine and of course it wouldn't address her need for supra-physiological doses of liothyronine.

She has already received a diagnosis of hypothyroidism, from Dr Skinner. This should be in her medical record, Dr Skinner would have written to her GP.

Her GP will probably be unwilling to prescribe liothyronine. I can understand this as they feel they should take guidance from endocrinologists. Unfortunately endocrinologists are useless. The only option I can see is that your daughter continues to self treat but asks her GP to monitor her - monitor her signs and symptoms rather than blood tests.

Your daughter should see if she can reduce her dose a tiny bit every month or two, just to confirm she is on the lowest effective dose. The nature of resistance to thyroid hormone is that different organs are affected to different extents, so you want to make sure her heart is not over stimulated. It would also be a good idea to do some exercise for her heart and bones to mitigate any effect her high dose liothyronine might have.

lucylocks profile image
lucylocks in reply to jimh111

Hi jimh111,

We do think she has thyroid hormone resistance, she did at one point get up to 200mcg. T3 and it was only at this dose she developed overdosed symptoms. She reduce to 175mcg, of these symptoms went away. She has reduced to 100mcg. to get onto a lower dose.

When she stopped the T3 for sixteen days she felt dreadful. she has now back on the T3 and has got up to 75mcg. but is not feeling too good, maybe it will take time for her to feel well again after the absence of T3 for sixteen days.

Glynisrose profile image
Glynisrose

Sack this doctor and get another!

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