Blood tests tomorrow should i take my levothyroxine beforehand

[ah2019]

Hi, I know I`m posting this a bit late but can anyone advise me the best way forward with a blood test i`m due to have tomorrow. I have been having problems with a sore tongue and lips and i`m having tests done for vitamin b, d, blood count and thyroid. Unfortunately the only appointment I could get was a 12.50, I usually take my Levothyroxine 100 mg at 6.30 am but don`t take it when i have a blood test usually as test first thing in the morning. My question is, as the appointment is in the afternoon, should I not take it till after my blood test. This will be quite a lot later than normal, and then if that`s the case will it be ok to then take the following morning as usual. Thanks everyone, and merry Christmas Amanda

[helvella Administrator Thyroid UK]

I'd still wait till after. Might be a bit too long, really, but if you take it at 6:30 or so, there isn't quite long enough for the peak to fade.

It should be fine to take it after the blood draw.

[ah2019 in reply to helvella]

Thank you

[humanbean]

It's too late now, but I might have been tempted to say that you should take your Levo the day before at 12.50, leaving 24 hours until your blood was taken for the test.

[ah2019 in reply to humanbean]

Thanks for reply, it was a short notice appointment, due to issues with my mouth. Thanks for response

[SlowDragon Administrator]

How much levothyroxine are you currently taking

What were last test results

TSH is far higher early morning. You run risk that TSH will be low

Definitely don’t agree to dose reduction based on just TSH

Median TSH graph

healthunlocked.com/thyroidu...

TSH daily variation

healthunlocked.com/thyroidu...

Very important when you test TSH ....

researchgate.net/publicatio...

“According to the current TSH reference interval, hypothyroidism was not diagnosed in about 50% of the cases in the afternoon.”

“Further analysis demonstrated inadequate compensation of hypothyroidism, which was defined in 45.5% of the morning samples and in 9% of the afternoon samples”

ncbi.nlm.nih.gov/pubmed/252...

TSH levels showed a statistically significant decline postprandially in comparison to fasting values. This may have clinical implications in the diagnosis and management of hypothyroidism, especially SCH.