How often are you meant to have blood tests (tft)?

Is there a rule of thumb for frequency of testing?

Within the last week or two I seem to need more meds. Today's morning t3 dose seemed to wear off a good 4 hours earlier than normal today, so I took my afternoon dose early then seemed to need more 3.5 hours later. Thinking it's time for a blood test.

I was last tested in Dec and results were good but haven't felt really well since Oct.

Last edited by

19 Replies

  • I was wondering this too as it looks like i'm going to have to self medicate, so I will watch for answers with interest! Thanks

  • No probs. :-)

  • I thought it was every 6/12 months once a stable dose and euthyroid status was achieved.

    If you are unwell and your dose has been changed, I believe it is every 6-8 weeks. When I stopped meds and resumed, GP tested me every 10 days until TSH & FT4 were to his liking.

  • Flippin' 'eck, where is your gp again? I'll be there when they unlock the door Mon morning. :-)

    That's good, many thanks. I may be getting these myself but no reason why I can't ask my gp. Wish I'd thought to do it when I asked for my last bloods (iron, ferritin, etc).

  • I suspect he may have been checking my compliance although he wasn't satisified with FT4 low in range so I may be maligning him.

  • Once stable it should be around once a year, saying that everytime i go and see a doctor with anything they seem to do a tft so when you feel you should have it tested ask for it. i had one in aug, oct, jan and they are the ones i can remember over the last year.

  • Thanks. I think I will ask for a phone appt to see what they say.

  • If you have been on medication and are 'stable' which they call euthyroid it's once a year. If you feel unwell in between with clinical symptoms you should ask for another blood test. Always get a print-out of the blood test as some doctors believe keeping us 'within range' is the right thing to day, but it isn't. If you haven't already had a Vitamin B12, Vit D, iron, ferritin and folate tested, ask for these to be done as we are usually deficient.

  • Thanks. Have just had vitamin/mineral tests above but didn't think to ask for tft. My gp has given up on treating my thyroid since I have been seeing an endo but endo has dropped me and I'm seeing someone private so gp may balk. Will see. :-)

  • Local hospital refuse to analyse bloods for TFT within 3 months these days. My GP intends to check mine annually, though I can hardly be described as stable currently. It must vary from place to place - another post code health lottery?

  • This is more or less what I anticipate, so I'm prepared to pay if necessary.

  • This is very odd. I have been exactly the same recently and had used up all my T3 doses today hours earlier than normal. My sign of needing more is aching body and feeling very cold. My temp has been very low all day until about 4pm. Last week I was feeling great and thought I had found the right doses at last. I expect you do need a blood test, although if you are on T3, I am not sure it means much and usually freaks out GPs, so I am lying low.

  • Yes, similarly I thought all was well in Oct - I felt good all summer and great in early autumn - then I seemed to wobble a lot between hyper and hypo, so my dose was changed a number of times. I'm actually on t3 and t4.

    I have been tweaking it in tiny ways - taking an extra crumb of t3 if feeling flat for example - but today was completely different. Took my 'afternoon' dose at 12 instead of 4, then needed more 3.5 hours later, then 2 hours after that I felt like a zombie again.

    Like you I worry that the tft is useless but I worry equally that I will be overdosed and not know. :-) My temp/pulse tend to be okay unless I am on far too much or too little meds so I lack confidence in my own ability to figure out what's going on. :-(

    Unless I was feeling well in which case I'd fight for my dose. :-)

  • Have you tried checking your blood pressure - there is a pattern to mine - best when euthyroid, both raised if hypo, upper figure only raised if hyper

  • Hmm, good idea. Usually my bp is low. Would this make a difference? Thanks for this suggestion.

  • Just a thought - in the past there were a couple of batches of UK liothyronine that seemed to be lower potency. Every time I go to the pharmacy I ask for alternative batches, but each time they keep trying to give me pots with the old batch number so some of these must still be in stock. If you have a pot with a different batch number to the one you are using, it might be worth switching to see if this makes a difference. Sandra

  • Many thanks Sandra but I've been using the same bottle maybe for two months and it isn't from the UK. This is good to know though and I hope others take note. Have you filled out a yellow card? Might be useful for the manufacturer to know.

  • I filled one in at the time. It was quite a while ago now. I hope you get to the bottom of the fluctuation. Sandra

  • Good for you for reporting it. Thanks for your reply. :-)

You may also like...