T3 suppression test

[Blueskyyy]

Hi

Could anyone please explain what is the T3 suppression test for ?

and how the patient gets prepared for this test ?

Thx

[shaws Administrator]

I am not medically qualified but think a T3 suppression test is to confirm whether you could be hyPERthyroid.

[Blueskyyy in reply to shaws]

Yes, but how is the procedure ?

Are patients asked to take t3 immediately before the test ? Or they must leave at least 8 hours between the test and last t3 dose ?

[MaisieGray in reply to Blueskyyy]

Its a test used to diagnose difficult cases of hyperthyroidism, but largely replaced nowadays by the thyrotropin-releasing hormone stimulation test. As I understand it from a lab descriptor I read, "Triiodothyronine (T3) is administered for a week to 10 days, and a reduction of its uptake by the thyroid gland to less than half of the initial uptake is a normal response". But if you have been informed that it is being carried out, you should ask the clinic or whoever has ordered it, for exact details of the protocol being followed, in case it differs from more general guidelines.

[greygoose in reply to MaisieGray]

I find that very strange, because I didn't know the thyroid uptook T3, anyway. Surely it's iodine that is taken up by the thyroid, not T3. I can't find any lucid explanation of the test and/or what it's supposed to prove, anywhere.

[MaisieGray in reply to greygoose]

Exactly! 🙂 Which is presumably is why it has generally been superseded by the TRH stimulation test. It's very odd for sure.

[greygoose in reply to MaisieGray]

Thank you. I thought it was just me! lol

[MaisieGray in reply to greygoose]

Definitely me too, so I hope someone else can shed some light on it!

[greygoose in reply to MaisieGray]

Yes, it would be interesting to know what it's all about. Blueskyyy , when you have more information, do let us know.