My wife is currently on 50mcg Levo taken last thing at night, and 10mcg Lio taken when she wakes up. She is currently feeling quite good. Her friendly Endo has request a TSH, T3, & T4 test this week. Should she take her meds the night and morning before the test?
I think the answer is no, but welcome your comments.
If your wife was taking levo only, the advice on here is usually to not take it in the 24 hours before the blood draw. Instead, it should be taken immediately after the blood is taken. So, on the day before the test your wife wouldn't take any levo at all, on the day of the test she would take 2 doses - one after the test and one at night as usual.
If your wife was taking T3 only, the advice on here varies from - don't take it for 24 hours before testing, or 12 hours before testing, or probably a few other suggestions. Clutter suggests that you could add 20% to the actual test result for Free T3 if you stopped taking it for 24 hours, and add 10% if you stopped for 12 hours, to get a realistic figure. T3 doesn't hang around in the blood stream that long, which is why 24 hours or 12 hours without it will give you quite a low figure.
If your wife is being prescribed T3 then you may want to keep the Free T3 figure low to avoid it being taken away. If your wife is self-medicating then she may not care too much about keeping the result low.
Everything I've said above of course, is aimed at people taking one or the other - levo or T3. If someone is taking both? Err... I don't really know what to suggest.
The only reason for all these shenanigans is that doctors don't trust patients, don't care about their symptoms, and don't know how time of dose affects results.
Take the levo the night before it will make no noticable difference to her TSH and fT4 results. If she is having the blood drawn in the afternoon I'd take the liothyronine in the morning, if the blood is being taken in the morning then postpone the morning liothyronine dose. Since she is taking the liothyronine once daily it will be difficult to get a realistic fT3 result due to its short half life of one to two days. Having said that her dose of 10 mcg is quite small and will not have a great effect. It is important to avoid taking the liothyronine within two or three hours of having the blood drawn. I did that once and got silly results.
Not what you asked but she might find she does better if she splits the liothyronine into two doses or takes it in the evening. My experience has been that the night time T3 levels help with good quality sleep and alertness the following day.
You might find this article of interest :
recoveringwitht3.com/blog/w...
The link was posted by Hidden earlier today.
I also wanted to add that I disagree with jimh111 . If your wife relies on her doctor for thyroid meds then everything you can do to get the results you want should be done. The alternative is getting dose lowered by the doctor inappropriately.
Don't take meds for at least 24 hours before blood test and try to make the test as early in the day as possible, 8 - 8.30am would be a good time. Taking T3 will lower the TSH result and that isn't what you want.
Let us know the results and hopefully your wife will still be on the dose that is making her feel well.
" She is currently feeling quite good". "Her friendly Endo" ... It seems perfectly reasonable to treat this helpful doctor with respect. If you distort the blood test results by holding off taking the hormone for a day it may well lead to her dose being altered inappropriately and she may no longer 'feel quite good'. You will never get to know your actual hormone levels.
I understand patients want to fiddle the results when it is the only way they can get treated but if you are being treated well there's no sense in misleading your doctor.
If you want to fiddle the blood tests then simply skip your hormone for a week or two, or send someone else for the blood test. If you don't trust the doctor don't go to them, buy your medication on the internet. The doctor has responsible for your care, they have reswwponsibility if anything goes wrong. If you have early signs of e.g. atrial fibrillation they cannot spot it during a consultation if you have interrupted your treatment.
If my wife has a test without taking meds in the last 24 hours, I shall tell the Endo anyway, as he has not stipulated either option.
Levothyroxine / Liothyronine combination advice
Dosage of Liothyronine and Levothyroxine
Levothyroxine and blood test 
Blood test due - palpitations 
