Hi all! I started taking 10mcg Liothyronine a few days ago having been prescribed them by an endocrinologist. He made a review appointment for me in three weeks time. Is this too soon? Should I rearrange the appointment for a later date or is that not necessary?
I’d also like to know the best way to approach the next appointment. I’m aware the advice is to stop levo 24 hours prior to a blood draw, t3 8-12 hours prior to it, that is should be fasted and as early as possible. However, the appointment is at 3pm and likely that the bloods will be drawn after that. (Clinic only runs in the afternoon). What’s your advice re timings then? I’m not sure I’ll be able to fast all that time as I get very dizzy/shaky if I don’t eat. Last time bloods were taken I’d had meds early in the morning, wasn’t fasted and it was nearly 4pm. Maybe I should do the same again for consistency?
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Mickeydooley
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Personally I'd want to wait 6 weeks, that gives time for levels to settle down.
As for the blood test, I would consider asking your surgery to do it a few days before your appointment, collect the results from the receptionist and present them to the endo with "I thought it would be more useful for you to have my results to discuss at this appointment so I asked my GP to do them". You can then do the test under the right circumstances with the correct timing.
Thanks for the reply. I tried that the last time I was there. In fact, my gp insisted that I got them done a week prior to my appointment (which I did according to recommendations on here) so that I had them to take to him but he redid them anyway! Don’t think he even looked at the ones I’d had done in the surgery. I gave him my medichecks test results which he looked at and prescribed me the T3 based on those. I’ll see if I can postpone the appointment for a few weeks.
In fact when I questioned him on the reliability of tests done at that time of day and having taken my meds etc he told me it was best that way as he’d be redoing the tests at the same time each visit.
Personally I would so all bloods are done same time after meds regardless of time of day. Tsh may be lower than in morning but on t3 should be really low anyways. Xx
Funny! I just looked at previous results medicated and unmedicated and Tsh was actually only very slightly higher when unmedicated! (0.338 as compared to 0.31 medicated).
The time gap is the same whenever you have the blood test. The time gaps quoted are so that you get the normal circulating level.
If you take Levo or T3 any longer than the time gap mentioned, you will get false low FT4/FT3.
If you take Levo or T3 too close to the blood draw then you get false high FT4/T3.
The early morning blood draw and fasting ensures the highest possible TSH (as most doctors tend to dose by TSH). TSH is highest at midnight, lowers throughout the day, the lowest point being about 1pm, then gradually rises again. See first graph in this thread:
Great info. Thank you! I’ll adjust my timings to ensure that levels are optimal. Not a lot I can do about the timing of the appointment so TSH might be lower than it should be and I’ll try to make that point to the endo. I’m assuming that my TSH will be almost non existent anyway given that I’m now taking T3. It was low before and he did comment that he’d have to keep an eye on it!
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