GP tests TSH only and want to reduce dose after... - Thyroid UK

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GP tests TSH only and want to reduce dose after its taken a year to get to this level - what factors affect TSH?


So GP (receptionist) called this morning after blood test on Friday. Blood test shows I am "overmedicated and need to reduce from 100mcg to 75mcg"

Blood test wasn't for thyroid monitoring but type 1 diabetes monitoring so TSH only no T3 or T4.

I said no as my brilliant endocrinologist prescribed this dose and I don't believe the GP should interfere especially as no testing of T4 and T3.

I should add I do have Hashimotos (Autoimmune). Last year in August I felt all the symptoms of overmedication and reduced Levothyroxine from 100mcg to 50mcg. Since then as T3 has been right of the bottom of the range so I've increased Levo slowly as that's all my body can tolerate, to quick and I get symptoms of overmedication. I have no palpitations/high BP/tremor/waking up weak and shaky as I had before on 100mcg. I actually feel ok - starting to lose weight, less tired etc.

So am I correct in think that TSH alone is utterly useless? I need T3 and T4 testing before changing dose?

And are there any other factors that might explain the low TSH? I just has a very nasty stomach bug? I am in a state of ketosis will that effect results? The heat? Hashimotos flare?

T3 at last test (9th April) was 3.9 (3.1-6.9) Up from 3.7 in Jan

TSH - April 1.34 (0.27-4.2) was 1.6

T4 - April 20.9 (12-22) was 17.7

Since April have adopted the Autoimmune Protocol diet (was already GF as coeliac) so this could have aided conversion?

Thank you for your time.

3 Replies

Correct, just testing TSH is completely inadequate when on Levothyroxine

For full Thyroid evaluation you need TSH, FT4, TT4, FT3 plus TPO and TG thyroid antibodies. Plus very important to test vitamin D, folate, ferritin and B12 as low levels of any of these tend to lower TSH

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.

All thyroid tests should ideally be done as early as possible in morning and fasting. When on Levothyroxine, don't take in the 24 hours prior to test, delay and take straight after. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)

As you are coeliac and Hashimoto's presumably you take bucket loads of supplements

Helpful if you say which ones and dose

Firm but polite refusal to reduce dose without full testing and revaluation by endocrinologist

GP is not thyroid expert

in reply to SlowDragon

Thank you very much for replying and many apologies for taking so long to thank you.

Apparently the GP can't speak to me until next week so have written her letter also cc-ed my endocrinologist.

I am fuming that the same GP who wouldn't refer me to endocrinologist and put all my symptoms down to being diabetic and actually said "One blood test doesn't prove anything" thinks she has the right to change my medication dose whilst costing me so much in private fees and blood tests. Argh!

Anyway, I've asked for all the blood tests you have recommended - I'm actually looking forward to the GPs response!

Thanks again.

in reply to Kes8

If your doctor dismisses vitamin levels as irrelevant suggest a print out of this might be useful

See Box 1. Towards end of article

Some possible causes of persistent symptoms in euthyroid patients on L-T4

You will see low vitamin D, folate, ferritin and B12 listed

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