Blood Test

[mummytina]

Why shouldn't you take your thyroid tablet before a blood test?

Tina

[RedApple Administrator]

Levothyroxine is at it's peak level in the blood around 2-4 hours after ingestion. So taking your dose before the test might give a high FT4 reading, which, if over the lab reference range, could lead your GP to conclude that you are over-medicated and thus reduce your dose of thyroid medication.

So, always try to get your thyroid test done early in the morning, and don't take your tablets until after the blood has been drawn.

[RedApple Administrator in reply to RedApple]

In case you are now going to ask why you should get your blood test early in the morning, the answer is because this is when your TSH is at it's highest, as referenced in the blog that has just been posted here

thyroiduk.healthunlocked.co...

[Jackie]

For years most vets have refused to test pets for thyroid if they have had the meds that day. Unfortunately most doctors are not so enlightened. MY GP does not like it when I quote that!

Jackie

[shaws Administrator in reply to Jackie]

I think most hypo patients would get proper diagnoses and meds from the Vet.

[Jackie in reply to shaws]

Oh, So true. My son had such wonderful treatment for his cat when Hyper!

Jackie