Going for a blood test at 4pm, do I take/not take my levothyroxine?

[S2017]

Hi,

Hope everyone is doing well. I am going for my blood test which I think is going to be late-evening (awaiting confirmation).

I have heard in previous forums to stop B-vitamins for 1 week (due to Biotin interfering with results) which I can do.

I had wanted to ask on the day of the blood test, do I take my levothyroxine on the day itself(I normally take it between 8-9am)?

I'm confused as from what I understand, levothyroxine is a daily pill, effects I guess last 24 hours, so if I don't take it in the morning of the test, wouldn't it be expected for my TSH to be high?

I have recently developed heart palpitations which I don't know now are anxiety or thyroid related. If it is thyroid related and the advise is to not take levothyroxine before drawing blood, then should I take after?

Many thanks to anyone reading and helping me with my query.

[Jaydee1507 Administrator]

There should be 24hrs between taking your last levo and a blood test. That said, noone would recommend getting a test done at 4pm as TSH varies throughout the day and likely to be lower at 4pm and your meds will be adjusted according to that value. The best time to get a blood test done is 9am so that TSH is at it's highest.

Have you had your key vitamin levels tested lately? Your iron has been on the low side before and is often responsible for odd heart rate, palp type symptoms.

[S2017 in reply to Jaydee1507]

Hi, thank your for your reply, could not reply earlier due to internet issues. Will try re-booking this for early morning and yes it will test key vitamins. Thank you.

[SlowDragon Administrator]

Rebook blood test for 9am …..last dose levothyroxine 24 hours before test 

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine

 

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested.

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options and money off codes

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

Only do private testing early Monday or Tuesday morning.

Watch out for postal strikes, probably want to pay for guaranteed 24 hours delivery 

[S2017 in reply to SlowDragon]

Hi, thank you for your reply, I am going to try to re-book to the earliest slot tomorrow morning. I managed to get this on Medichecks and some else posted on a 20% discount using code HALLOWEEN20 which is a good saving. Thanks and sorry for the late reply - had connectivity issues with my laptop.

[Regenallotment]

Remember it’s ok to cancel an appointment and rebook. 😊 don’t be steered into a blood draw that is pointless for getting what you need. 🦋💚🦋

[S2017 in reply to Regenallotment]

Great, thank you. Planning to re-book to a morning slot tomorrow.