Cortisol blood test - leave T4 dose out? - Thyroid UK

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Cortisol blood test - leave T4 dose out?

cal1971 profile image
3 Replies

I have my cortisol blood test in the morning ( 9am) as requested by the endo prior to deciding if they will see me (I suspect will say it's fine so will get out of doing a T3 test...grrr).

I take my levo at bedtime ( about midnight) so should I not take it tonight? I know people have said on here not to take meds prior to blood tests but wondered if 8 hours is enough?

Thanks in advance.

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cal1971
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nobodysdriving profile image
nobodysdriving

I would skip it purely for the reason that they may decide to also test your thyroid 'while you are there'

cal1971 profile image
cal1971 in reply to nobodysdriving

No, they don't want to do that,as it hasn't been 6 weeks on the increased levo yet, I have that booked in for 2 weeks time ( the good old TSH test... :() so tomorrow is just a blood cortisol test at the request of the unseen endo....hmmm.

nobodysdriving profile image
nobodysdriving in reply to cal1971

Levo does not interfere with the cortisol test, however still make sure they won't do the thyroid function, I have heard it a million times that they don't plan to do them then they still do!

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