Supplements and blood test

[Lahodges10]

Hi all again! So sorry one more post. I am having bloods tomorrow... TF1 and XFT as well as electrolytes as I have low potassium. I’ve been taking vitamin c, Ashwagandha, a probiotic and gaviscon for about two weeks. This was before the doctor mentioned thyroid and I thought I was losing my mind, I really needed to try something to soothe my agitated mind and body. Will these affect my bloods tomorrow? I can leave them for today and tomorrow if needed but don’t want the bloods to be scrambled but I don’t think I can’t wait for the test as I need to know what’s going on. Thank you. I realise I sounds like a crazy person 😭 Lauren xx

[SeasideSusie Remembering]

The only supplements that it's essential to leave off are:

Biotin (B7) or a B Complex containing Biotin. This should be left off for 7 days before a blood test because many labs use Biotin in the testing procedure and if we also take Biotin as a supplement then it can give false test results.

Iron supplements (or iron rich food) should not be taken for 7 days before testing iron/ferritin.

B12 - if wanting a baseline B12 level then we should leave off any B12 supplement for 4-5 months.

Anything else, just don't take on the day of the test until after the blood draw.

As you're having a thyroid function test, your blood draw should be no later than 9am and you should fast overnight from evening meal/supper, it's OK to drink water before the test but no other drink (coffee affects TSH). This gives the highest possible TSH when looking for a diagnosis of hypothyroidism. If your test is booked for later than 9am I would cancel and rearrange it.

[Lahodges10 in reply to SeasideSusie]

Thank you so much for your reply. I’m being tested for hyper active thyroid so would I still need an early appointment? My appointment is 12pm as that was all they had and I was desperate. My gp also didn’t tell me I’d need to fast so thank goodness you did! I just want the right result so I can get sorted, my gut feeling is my thyroid is out of whack and I’m desperate for answers 😭 thank you so much for your reply 😊

[SeasideSusie Remembering in reply to Lahodges10]

That advice is for people who are looking for a diagnosis of hypOthyroidism, as mentioned. Timing and fasting are recommended to give the highest possible TSH which is needed for a diagnosis of hypOthyroidism.

If your GP suspects hypERthyroidism then your TSH would be very low or suppressed and your FT4 would be over range so the timing/fasting advice doesn't necessarily apply.

If I were you I'd just keep this appointment and check with the nurse exactly what thyroid tests are included. It would be most helpful in diagnosis if the following are included:

TSH

FT4

FT3

Thyroid antibodies

Thyroid tests are usually back within 24-48 hours, so give it 3 or 4 days and then pop back to the surgery and ask the receptionist for a print out of your results. Post them on the forum for members to comment.

[Lahodges10 in reply to SeasideSusie]

Thank you so much. That is hugely appreciated. I’ll post results as soon as I get them. Lauren😊