Thyroid test at GP's

[Mia09]

Can you let me know why you say not to take your Levothyroxine before a thyroid test? Wouldn't this raise your TSH and therefore you may be prescribed more medication than you need.

[SeasideSusie Remembering]

TSH is normally very slow to respond to dose changes, it may not rise at all if it has been suppressed for a long time.

We advise taking last dose of Levo 24 hours before the blood draw. This should give a result which reflects the normal circulating amount of FT4. Any longer and you will get a false low FT4 result. If we take Levo before a blood test, the test will reflect the dose just taken and we will get a false high FT4 result.

[Mia09 in reply to SeasideSusie]

OK, thanks, although my GP has said on numerous occasions that the NHS will only check the TSH level. It looks as if I'll have to have the test done privately to check everything.

[SeasideSusie Remembering in reply to Mia09]

my GP has said on numerous occasions that the NHS will only check the TSH level

This varies and is probably dictated by the CCG. Some only check TSH and if that is in range then nothing else is tested. Some test TSH plus FT4. I'm in Wales and because my TSH is always suppressed I get TSH, FT4 and FT3 done every time.

There are hundred of members here who do private tests with one of our recommended labs because they can only get TSH done with their GP.

[SlowDragon Administrator in reply to Mia09]

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Ask GP to test vitamin levels and thyroid antibodies if these haven’t been tested yet

You may need to get full Thyroid testing privately as NHS refuses to test TG antibodies if TPO antibodies are negative

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

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

thyroiduk.org.uk/tuk/testin...

For thyroid including antibodies and vitamins

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 special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random