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Free T3 decreased

Hello, my doctor dx me with subclinical hypothyroidism and PCOS after my labs a couple months ago. I felt amazing after taking the Levothyroxine (50mcg once daily) but began feeling really run a few weeks later so she ordered a full work up and included the TSH within Reflex to FT4 and free T3. Comparing the results, they both lowered TSH w/reflex is now 1.73 and my free T3 is 2.9. Per labs this is still within normal range albeit the lower end for Free T3. My doctor is out of the office for the week and I thought to come here for some insight as I am completely new to this.

My Vit D is also at 18 and she put me on that weekly as well as Spironolactone 50mg daily to lower my testosterone, which is now at 15. I have to wait for my estrogen and progesterone numbers until a certain cycle date but I guess my estrogen was low due to a higher testosterone that PCOS seems to have caused.

Reading up on this makes me even more confused and I plan to talk to her about it all next week but from the responses I have read you guys are extremely knowledgeable and could possibly give me some insight?

Thanks so much!
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Avatar universal
The first thing I want  to emphasize is that hypothyroidism is not just low thyroid levels.    The correct definition for hypothyroidism is "insufficient T3 effect in tissue throughout the body due to inadequate supply of, or response to, thyroid hormone".  So it is the Tissue T3 Effect that determines your thyroid status.   Since there is no biochemical test that can directly measure Tissue T3 Effect, we have to resort to the use of indirect measures.  So diagnosis for potential hypothyroidism should start with a full medical history, followed by an evaluation for symptoms that occur more frequently with hypothyroidism, and finally extended biochemical testing.  

You have numerous symptoms that occur more frequently with hypothyroidism than otherwise.    Unfortunately your testing did not include some very important tests:  Free T4, Reverse T3, B12 and cortisol.   The TSH test is useful for diagnostic purposes only when  it is at extreme levels.   The lab order specified TSH w/reflex to FT4, so FT4 was not done.  In diagnosing an  untreated person FT4 is even more important than FT3, since in the absence of adequate FT4 the body will convert extra T4 in an effort to maintain body functions.  In addition, it is useful to test for Reverse T3 at the beginning to make sure T4 is not being converted to excess RT3.  

From the definition of hypothyroidism, the response to thyroid hormone mentioned is affected significantly by cortisol, Vitamin D, B12 and ferritin.  You were not tested for cortisol and B12.  Your Vitamin D and ferritin were extremely low.  D should be at least 50 ng/mL and ferritin should be at least 100.    Ferritin is considered as a pre-cursor to serum iron levels, and your serum iron was also on the low end of its range.    

So at this point it is not clear  if your hypothyroid related symptoms are due to primary or central hypothyroidism, or to inadequate response to thyroid hormone resulting from other variables.   Your TSH is higher than would be expected with central, yet not high enough to clearly indicate primary hypothyroidism.  So it would be useful to test for Thyroid Peroxidase antibodies, and Thyroglobulin antibodies, which are related to Hashimoto's Thyroiditis, just to put that to bed.   You also need to get tested for Free T4, Reverse T3 and Free T3 from same blood draw,  cortisol, and B12.  

Note that even though you got a short term benefit from the 50 mcg of Levothyroxine, that is not the usual effect.   The usual effect is little to no change in  thyroid levels and symptoms.  That is because thyroid med is not additive to your prior thyroid hormone levels.  The med causes the pituitary to reduce TSH levels and thus reduce the output of natural thyroid hormone.  Since serum thyroid levels are the sum of both natural thyroid plus thyroid med,  only when med dosages have been increased enough to essentially suppress TSH, will further increases in med dosage start to raise FT4 and FT3 levels.    Note the conclusion in a recent, excellent scientific study:  "Hypothyroid
symptom relief was associated with both a T4 dose giving TSH-suppression below the lower reference limit and FT3 elevated further into the upper half of its reference range."  

I haven't said anything about the PCOS.  Being male I am not very familiar with it.  Also, I wondered if the basis for that diagnosis might have also come from some of the symptoms that you have that could also be associated with hypothyroidism.  

So I highly recommend getting the additional tests done and then re-assess your diagnosis and treatment.   Do you think you can get those done?  If you want to confirm what I have recommended, please click on my name and then scroll down to my Journal and read at least the one page overview  to a full paper on Diagnosis and Treatment of Hypothyroidism: A Patient's Perspective.  
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Avatar universal
Yes, I only began the meds after the first test results. Ive been on them since May 21st I believe.

As for the testosterone she said even though it was in normal range it is possibly bringing my estogen down so she wanted to see if this would up that value, from my understanding anyways

Vitamin D I think is 50,000 1 tablet weekly

Iron from 6/27 is:

Total Iron is 61 range 40-190
Iron binding capacity is 410 rang 250-410
Ferratin is 28 range 10-154

My hemoglobin in 11.9 range 11.7-15.5
Hematocrit is 35.7 range 35-45
MCV 84.8 range 80-100
MCH 28.3 range 27-33
MCHC 33.3 range 32-36

So all within range




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Avatar universal
Before further discussion I just want to confirm that you started taking the thyroid med after the first set of test results.  Also I don't really understand why the doctor wanted to reduce your testosterone level, since it was only sightly above the middle of the listed range.  

What amount of Vitamin D are you getting weekly?   Also please post the iron test panel results and ranges.        
Helpful - 0
Avatar universal
Thanks for responding... symptoms are:

Extreme Fatigue
Always cold
Dry skin
Weight gain
Muscle weakness
Muscle aches, tenderness and stiffness
Pain, stiffness or swelling in your joints
Heavier than normal menstrual periods
Thinning hair
Sometimes constipation but my diet could be culprit with low carbs
Bad memory
Low libido

Headaches/migraines may be due to hormone levels, we are looking into that.

As for bloodwork:
5/13/18
D is 18 range 30-100
TSH w/reflex to FT4 was 3.16 range .40-4.5
T3, free was 3.4 range 2.3-4.2
Vit B12 425 range 200-1100
DHEA dulfate 153 range 23-266
FSH 4.4 range 1.5-9.1
Progesterone 3.1 range 2.6-21.5
Estradiol 69 range 56-214
Testosterone was 25 range 2-45

Lab tests from 6/27
TSH w reflex to FT4 is 1.73 same range
T3 free 2.9 same range
Testosterone 15 same range
She also did a CBC, CMP and iron levels this time all within range although all iron levels are on the lower end






Helpful - 0
Avatar universal
In trying to assess a person for potential hypothyroidism, the most important consideration should always be symptoms.  So please tell us about all symptoms that you have.  
After symptoms, comes biochemical tests compared to reference ranges.  So please post all your test results and their reference ranges shown on the lab report.  
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