Thyroid UK
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I was started on Erfa 30mg, 5 weeks ago, by a private doc. he has advised me to test in the next couple of weeks.

He said to take the Erfa tab. first thing in the morning , then get the blood test mid-morning, and this will tell him how well the 30mg is doing.

When I said the advise I had read, was to test early, on an empty stomach, with NO thyroid 'till afterwards, he disagreed. Said he wanted to know the effects of taking the hormone.

I don't know which way to do it now. Thank you for any thoughts.

3 Replies

Stoneym, most people want to know the normal circulating hormone levels which is why they're advised to leave 24 hours between last dose and blood draw. Your endo's way will measure the T4 and T3 peaking after ingestion. T4 and T3 can peak in the serum for up to 6 hours.

1 like

Taking meds before a blood test is not a good idea. The results are skewed because the nly thing that gets measured is whats in the blod stream.


Thanks for your reply Glynisrose. I don't like going against advice that I'm paying for!


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