I had my thyroid levels checked recently after being on my current increased dose of levothyroxine 125mcg for 8 weeks. I was previously on 100mcg, which was my starting dose as I've recently been diagnosed as having hypothyroidism.
I read on this forum that I should take my last dose of levothyroxine 24 hours before getting a blood test at 9am. I wasn't thinking clearly and messed up the timings and I ended up having my blood tested 36 hours after my last dose of levothyroxine. I take my medication at night around 8.30pm so by skipping my dose the night before the blood test it ended up being 36 hours.
This has obviously skewed my results and my t4 and t3 came out lower than when I was on 100mcg. Although when I was tested when I was on 100mg I didn't delay my medication as advised on this forum so I know I can't compare those results to my current results on 125mg.
My question is can I now retest and how soon. I am so annoyed with myself as I'm trying to get my thyroid levels stable to try and conceive. Unfortunately I had a pregnancy loss in January that they think was related to my undiagnosed hypothyroidism.
My results were:
T4 13.8 10.8 - 25.5
T3 2.9 3.1-6.8
TSH 2.54 0.27 - 2.4
Thanks
Written by
Cassav
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Well, your FT4 is very low, so I doubt it would have been high enough even if you had left only 24 hours. And that time gap wouldn't have had any effect on the TSH or the FT3. Your FT3 is below range, and your TSH is too high, so you're obviously under-medicated.
As you're not changing dose, you can retest whenever you like. You only have to wait 6 to 8 weeks after a change in dose or brand of levo.
Thanks for this. My previous results on 100mcg are below and have dropped on the 125mcg dose. Although as previously mentioned in my post I didn't stop taking my medication 24 hours before the test and it wasn't at 9am:
T3 3.4
T4 19.3
TSH 0.83
Could it be an absorption problem? I've been working with a functional medicine practitioner due to SIBO/bacterial overgrowth and have been taking antibiotics/ antimicrobials/activated charcoal and probiotics. I thought that I was leaving an appropriate gap between what I've been taking and the levothyroxine but perhaps I've been a bit slack.
I also switched to taking my levothyroxine at night and I stopped taking it with lemon juice/apple cider vinegar as I was doing previously.
Also, I think that the brand they gave me was different but I'll have to check.
And finally, I did feel like my sleep deteriorated as soon as I upped my dose to 125mcg when on 100mcg my sleep finally improved. But this also coincided with all the other changes that I made.
Or could it be that my body just needs more levothyroxine?
Frankly impossible to answer any of your questions because we don't have any reliable results. When you get a new test, using the appropriate protocol, we'll know more about how to preceed.
Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
SIBO/Antibiotics likely to have affected levo uptake
Thank you for the information. Oh I didn't think about the sibo/ antibiotics affecting uptake.I tested for thyroid antibodies, vitamin D, folate, ferritin and B12 in May and just waiting for some of the results of my repeat tests. My B12 (from 484 to 620) and Folate (from 7 to 14) have improved.
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