Hi, I was diagnosed with hypothyroidism 9 months ago and still trying to get my Levo dose right. I recently heard that I shouldn’t take Levo for 2 days prior to my blood test. My test is on Friday (2 days time) so should I not take Levo today and tomorrow until after the test at 2pm?
Thanks so much!
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SleepingDisco
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thanks so much for taking the time to reply to my post. I usually take it between 6-7am. Based on all the replies I’ll definitely keep taking it, but hold off on test day until after my bloods have been taken (2pm)
And then make sure I book future tests for as early in the day as poss.
I’ve read some interesting articles about taking Levo in the evening and that it doesn’t make much difference to do so - do you know much about this?
Some people find taking levo at bedtime works better for them. Others don't. It can be convenient to take it at night, for example if you have other medications that need to be taken in the morning.
It is often suggested that bed-time dosing results in slightly better absorption. It also seems slightly closer to the pattern healthy people have.
I have always taken my levothyroxine at bed-time.
For that reason, I cannot compare with taking in the morning.
Before diagnosis, my sleep was badly disturbed. Typically, I would fall asleep fairly easily. Then wake up after something like half an hour to two hours. Once woken I'd be unable to get back to sleep - often till dawn, or at all.
Once I started on levothyroxine, my sleep slowly improved. By the time I was taking an adequate dose, bad nights were unusual - just an occasional night where I might wake up for a while. Now, after years, I sleep very easily and deeply and rarely wake at all. If I do, I get back to sleep quickly.
We have some who prefer it; we have others who prefer other times. See our poll:
I'm still getting my head around it all. I battled with my GP to increase my dose as I still had loads of symptoms on the 50mg and then 75mg doses I was initially and then prescribed. I've been allowed to try 100mg for 3 months - hence me wanting to get the blood test right on Friday as I'm worried he'll make me drop back down if the numbers aren't 'right'. He said there's a big risk of osteoporosis if I over-medicate on levo..
But I definitely feel a bit better on 100mg; the weight gain has eased a bit (although not reversing yet!) (I put on a 1.5 stone with untreated thyroid, and have never had to really worry about weight gain before).
Just the tinnitus now - it's so bad atm! Constant ringing in both ears - drives me mad!
it does indeed, thank you. And yes, I’ve heard (!) tinnitus is something that we just have to get on with unfortunately, regardless of Levo levels etc. 😩
Most want to measure FT4 when it is at its lowest daily level. If you take 1 dose daily ie every 24 hours then your low point will be at the 24 hour mark just before you take your next dose and it starts to build up again in your blood.
So you take your last dose of levo 24hours before your blood test if that is what you want to do.
The peak level of t4 in the blood comes 2 to 4 hours after you take a dose of levo. So it is best to avoid a blood test during peak time as it is unrepresentative of blood levels the rest of the day.
It is up to you to find what timings suit you, then stick with the same protocol for all your blood tests so you compare like for like.
Tsh is higher early morning so you will see advised here to get earliest blood test possible. However some surgeries dont do early morning thyroid tests. Also for some folks tsh is no longer important so we don't bother about having bloods done first thing. My blood tests are always around 2pm for example. I also split my daily levo dose. My longest gap in my daily 2 dose routine is 16hours so I leave a 16 hour gap between my last dose of levo and the blood test.
thanks for taking the time to reply to my post. Some really interesting info here. I always have my blood tests done at 2pm, but wonder if I should switch this to early am from now on…
If your doctor judges your dose by looking at your tsh rather than looking at ft4 and ft3 levels then you want to get the highest tsh you can. So early morning and only water to drink as some food and drink might lower tsh slightly. If like me the dr ignores the tsh then you can have later blood tests.
levothyroxine last at least 7 days in cells….but test looks at Levo in blood…..So your looking for 24 hour gap between last dose levothyroxine and blood test
Delaying an evening dose levothyroxine until morning 7-8 hours later than normal won’t affect TSH
And if normally split dose ….half morning and half bedtime it will make even less difference
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