FT3 FT4 Test 4 hours after taking Tirosint?

[KarmaMaya]

Hi, So I always have my thyroid labs taken in the morning on an empty stomach before taking my morning Tirosint dose. I currently take 75 mcg. My recent labs show TSH at .069 (.4 - 4.5) range and FT4 1.37 (.8-1.8) range and FT3 2.58 (2.2-4) range. I know my TSH is low but I don’t feel euthyroid. I have all the symptoms of hypothyroidism and yet my doc wants to lower my dose again. I have dropped from 100mcg to 88mcg to 75mcg. He tells me that my FT3 and FT4 numbers aren’t useful because those should be taken 4 hours AFTER taking my Tirosint. I can’t find anything on the forum or web that explains this perspective, other than that is when those numbers would peak. Can anyone clarify this for me? Thanks so much!

[SeasideSusie Remembering]

KarmaMaya

He tells me that my FT3 and FT4 numbers aren’t useful because those should be taken 4 hours AFTER taking my Tirosint. I can’t find anything on the forum or web that explains this perspective, other than that is when those numbers would peak. Can anyone clarify this for me?

Some doctors say this and it's puzzling because there doesn't seem to be any reason to test when FT4 and FT3 are at their peak after ingestion of thyroid meds, if we test using the time gap(s) advised here you get a measure of the more normal circulating level of hormone. It's probably lack of understanding/ignorance on the doctor's part.

My recent labs show TSH at .069 (.4 - 4.5) range and FT4 1.37 (.8-1.8) range and FT3 2.58 (2.2-4) range.

Your doctor is obviously using the TSH result to adjust medication which is wrong. TSH is not a thyroid hormone, it's a pituitary hormone, the thyroid hormones are T4 and T3 and it's only these that can tell us our thyroid status.

Your FT4 is 57% through it's range and your FT3 is just 21.11%, both too low in range and suggest that you should raise your dose of Tirosint, but those percentages also show us that your conversion of T4 to T3 is poor. Good conversion needs optimal nutrient levels so have you had Vit D, B12, Folate and Ferritin tested?

[KarmaMaya in reply to SeasideSusie]

Yes, vitamin D was just in the low end of the range at 35 range (30-100). Ferritin 72 range (8-252), B12 603 range (193-986). He also checked my prolactin level to see if the pituitary glad was malfunctioning 4.5 range (.7-31.5). No issue there. So conversion problem must be systemic. How much D should I take? Any other suggestions?

[SeasideSusie Remembering in reply to KarmaMaya]

How much D should I take?

Check out my post about Vit D supplementation and click on the link given to go to the Vit D Council website where you will be able to see how much D3 you need

healthunlocked.com/thyroidu...

[tattybogle]

Re. time of last dose ~ see the 3rd reply to this post ( then get GP to read that paper) :

healthunlocked.com/thyroidu...

[tattybogle in reply to tattybogle]

re. the lowering of your dose .. see this post .. shows TSH 0.04 to 0.4 had no greater risks than TSH 0.4 - 4 does .. ( risks did increase when TSH was lower than 0.04)

healthunlocked.com/thyroidu.... useful-evidence-that-tsh-between-0.04-0.4-has-no-increased-risk-to-patients-on-levothyroxine-as-long-as-ft4-and-ft3-are-in-range-.

[KarmaMaya in reply to tattybogle]

Thanks. Yes, I did share this with him and he didn’t care. He had me hold out my hand and placed a paper on the top of it. It trembled ever so slightly and he said, “See, over medicated !” I was convinced for a moment until I did the same thing with my husband and his hand showed the minutest of tremble as well. Hmmm, he doesn’t have thyroid issues and is as chill as you can get.

[jrbarnes]

I'm also in the USA and my advice is to find another Dr if they keep lowering it based upon TSH and doesn't feel the other tests are informative or valuable. There's too many Drs out there that care about more about your symptoms than labs. This Dr sounds very old fashioned and out of date. I see a functional practice registered nurse out of pocket for only $99 per visit and I decide how much I take and what works for me. As far as when you take the test all that matters is how you feel. Labs are just tools.

[KarmaMaya in reply to jrbarnes]

Thanks, good point. I asked the endo if he takes into account how his patients feel and he sort of dismissed my comment with a “sure I do, but you are clearly over medicated.” Humph. I will find a functional medicine practitioner.