Low TSH, increased Synthroid

allnurses Guide · Aug 30, 2009

Nope - low TSH means high T3/T4, so I'm not sure why you would add more T4 in the form of synthroid.

n_g · Aug 30, 2009

What if the pt has Sheehan's Syndrome? Then a low TSH means a malfunctioning pituitary and low T3/T4 levels.

Editorial Team / Admin · Aug 30, 2009

Yes. Patients who have survived thyroid cancer. They are at or near total suppression.

morte, LPN, LVN · Aug 30, 2009

Yes. Patients who have survived thyroid cancer. They are at or near total suppression.

but wouldnt they have and elevated TSH?

i would think it is a pituitary issue.....but there would be other blood work to doc a need, such as low T4

Editorial Team / Admin · Aug 30, 2009

I was just pointing out that, yes, there are clinical situations where the hormone can be increased even with low TSH. Increase to the point of at or near total suppression.

I would have to have a lot more information before actually advising in this situation.

kanzi monkey · Aug 30, 2009

Yeah, I was thinking perhaps a pituitary thing too. This is not for my own medical advice, btw. Just something I saw in the hospital that confused me (pt with low TSH, synthroid increased at that time--no T3 or T4 drawn, and no good endocrine hx documented that i could find).

Will look into it further.

silas2642 · Aug 30, 2009

What was the T3/T4 when you measured it? The TSH alone doesn't really tell you much. Also, how did the pt present and what was the PE like-- these are kind of important clues that you all have to put together.

Also, if you're not sure, you really need to be asking a physician before fooling around with someone's thyroid.

kanzi monkey · Aug 30, 2009

What was the T3/T4 when you measured it? The TSH alone doesn't really tell you much. Also, how did the pt present and what was the PE like-- these are kind of important clues that you all have to put together.
Also, if you're not sure, you really need to be asking a physician before fooling around with someone's thyroid.

Hi Silas,

I'm still working as an RN in a surgical setting, so my finding this was more incidental than anything. I would have loved to have ordered a repeat TSH, T3/T4, but I can't do that (and there was no recent T3/T4 result) . The patient has an endocrinologist who is not affiliated with the hospital, so I don't have access to her detailed thyroid history. As far as PE goes, her post-op status is probably somewhat different from her usual presentation/though she IS brady, and that seems to have been the case pre-op as well. Based on that, a little research on low TSH/thyroxine replacement (seeing that it is not, in fact, completely strange with certain conditions and based on certain histories), and trust that her endocrinologist is on the ball, I let it go and gave her her ordered synthroid without asking questions.

I can't wait to work as an NP. Curiosity around these things isn't really encouraged in my work environment since it is so busy, and it's sometimes frustrating to not have open opportunities to discuss my pt's--the pt's I'm caring for--in a way that helps me learn or satiates my curiosity.

Oh well. At least I have books. And you folk that take a moment to share your thoughts. Thanks!