Slightly low free t4

[awolever]

I have a slightly low free T4. It was at 1 and last test .88. My doc wants to put me on Levothyroxine .25. I’m wondering if this is necessary? It’s still in the normal range, but all the way at the low end.

Thank you!!

[gimel]

I  really have little to offer regarding your hormone results other than thyroid.  In that area you have symptoms that are typical of hypothyroidism.  Your Ft4 is always around the very low end of its range.  From your FT3 results it appears that your body is converting T4 to T3 in an effort to maintain body functions largely regulated by FT3.  When trying to assess a person's thyroid status, symptoms are most important, followed by FT4 and FT3 taken together, which in your case is too low., resulting in symptoms.

Looking also at your TSH level, it may be that your  hypothalamus/pituitary are not stimulating your thyroid gland adequately.  The best thing to do is to add thyroid med, as needed to relieve symptoms, which the doctor has done, although I would have started you on at least 50 mcg.   However, you need to understand that thyroid med will cause the TSH to drop, resulting in less output of natural thyroid hormone.  The net effect is no change in thyroid levels until TSH is low, and not affecting natural thyroid output any further.  The potential problem is frequently getting enough thyroid med to relieve symptoms will cause the TSH to become suppressed. Most doctor interpret this as being over medicated and will lower the dose, and you your symptoms will return.  

So you need to know if your doctor will be treating you based on TSH level, or symptoms, along with FT4 and FT3.   IF the doctor adjusts dosage based on TSH that is not going to work for you.  So I suggest that you give the doctor a copy of our paper in this link and ask to be treated clinically, as described.  

https://thyroiduk.org/wp-content/uploads/2022/10/Patients-Guide-Final-V5.pdf

Also would be a good idea to test for Vitamin D, B12 and ferritin.  For best results D should be at least 50, B12 in the uppere part of its range, and ferritin should be at least 100.

[awolever]

Thank you!

[gimel]

Those results are certainly in the low end of the range; however you cannot make a diagnosis based on that alone.  If other thyroid related tests were done, please post results and reference ranges.  Even more important is whether you are having symptoms typical of hypothyroidism, sos please tell us about any symptoms you have.  

Be aware that taking 25 mcg of Levothyroxine will do nothing for you.  If you are truly hypothyroid you should start on a higher dose.  From what you have told us I have reservations about your doctor, so there is a lot of info we need to give you.  but first let's start with the above questions.  

[awolever]

Thank you!

October 2021
TSH 1.39 Range 0.360-3.740 Normal
T4 Free 0.70 Range 0.76-1.46 Low

March 2023
Estradiol 13.7 Range 1.1-7.8 High
DHEAS 20.67 Range 0.76-15.2 High
Progesterone 88 Range 99-333 Low
Free T3 3.4 Range 2.1-4.2 Normal
Free T4 1 Range .8-2 Normal
TSH 2.4 Range .5-4.7 Normal

April 2023
Free T4 0.88 Range 0.82-1.77
TSH 2.4 Range 0.45-4.5
Estradiol 37.2 no range listed
Progesterone .3 no range listed

[awolever]

My main reason for having the thyroid checked was due to possible peri menopausal symptoms: fatigue, some night sweats, hot flashes, weight gain, heavy periods, muscle aches, slight memory issues. I figured all this was due to getting older. I’ll be 42 in two days.