Effects of water pills

[Ga7]

What effect if any would Hydrochlorothiazide have on lab results, of TSH and free 4 and 3..Seems that when I get my labs after being on the water tabs they are lower. My question rises from I was on 150 synthroid and my labs would bounce from 5 to 7 TSH T4 free about 1.5 so while off the water tabs. I was still getting jitters so I switch to 100 levoxyl for 6 to 7 weeks and I had been on water pills during test and my labs came back with TSH of .08 and free T4 0f 1.7 and no jitters now. So it seems that lower dose with different brand got me right, but afraid the labs were miss lead do to water tabs. I thought it would make my labs in the high range. Your thoughts on this and the warning told that water pill can effect Thyroid panel test.

[Mark Lupo, M.D.]

While this is reported in the handout on HCTZ, there is not much published in the clinical thyroid literature about an effect on thyroid levels and I have not noted in practice that HCTZ alters thyroid levels in any significant way.  So it is unclear if it had an effect in your case.  An US could be done to see if there is any significant thyroid tissue -- that would not prove it is active tissue, but be a starting point to see how much is there.

[Ga7]

And to add I do not have any thyroid TT done 20 years ago. But never after that did US to confirm no activity,, I was told that I might had minor thyrosis since I did not take any meds for 15 of those years and had no symptoms. And now what little glad might be left have reactivated and cause for lower dose now. I was up to 200 Synthrod at on time and worked my way back down to this 100 levoxyl now My TSH one year ago was 118 on no meds, but told my TSH 18 years ago was 300, so it came down with no meds. Just started back taking last year.