Too radical a doseage change?

[StephanieTiff]

I have Graves and irradiated thyroid 40 yr ago. On 150mcg until symptom of hyper. Labs were: T4 was normal, Free T3 was 1.67 and TSH .25
   My dr said I was too high and reduced levotjyroxine to 112mcg.
  I'm sleeping a lot and worried about gaining weight. Anyone had their doseages reduced so much at one time?
Thank you!

[gimel]

T4 has a half- life of about one week, which means that serum levels will show about 50% of the change in the first week, and 75 % in the second week, etc.  So in 4 weeks your serum level would reflect about 93% of the reduced dosage.  That is why you did not notice any significant effect right away.  You need to get the doctor to re-test your Free T4 and Free T3 levels and increase your med.  When you are close to optimal levels, changes in med dosage should be in small increments, not 25%.  

While you are getting tested again, I also suggest tests for Vitamin D, B12 and ferritin.  Hypo patients are frequently too low in the ranges for those.  D needs to be about 55-60.  B12 in the upper end of its range, and ferritin should be about 60 minimum for women.  D and ferritin affect metabolism of thyroid hormone.

[StephanieTiff]

Thank you for your feedback! I hadn't known about figuring percentages. I've been on low dose for almost a month and the sleepiness had just started this week. My dr is a DO and ordered heart stress test etc, for the skipped beats and palpataions.

[gimel]

Those symptoms you mention can be related to either hypo or hyper, but with the Free T4 over the range limit and Free T3 at 81% of the range, it appears more likely to be hyper.  So, now you are sleeping a lot and have palpitations, which I imagine is due to flipping over into hypo.  The reduction in your med dosage from 150 down to 112 is a 25% drop, which is a whole lot all at one time.  Since all your thyroid hormone comes from the med, I think that the 25% reduction has likely dropped your levels too much.  How long have you been on the reduced dosage?

[StephanieTiff]

Yes at the 150 I had insomnia, hair loss and heart palpitations.
T4 free range (L=0.70 H=1.48 mine= 1.67
T3 free range L=1.45. H=3.48 mine =3.10
TSH.    range L=0.35   H=4.67 mine=0.25

Now I'm sleeping 12-14 hours-still hearty skipping beats

[gimel]

We need to know the Free T4 result and reference ranges for the Free T4 and Free T3.   Also, were you having any symptoms while on the 150 mcg?