Low TSH & Low Free T4

[Lilybsmommy]

Hello! I was diagnosed with hypothyroidism about 3 years ago. I was taking a compound medication. Recently, I went to my PCP after gaining weight rapidly and experiencing extreme sleepiness and irritability.

My labs came back:

TSH <0.01 L
Reference 0.27-4.20

Free T4 0.65 L
Reference 0.93-1.71

The research I have been doing shows that I may have secondary hypothyroidism caused perhaps by a pituitary tumor. Unfortunately, the specialist my PCP referred me to is booked until the end of July. I would love to get anyone's opinion on anything else I may have so I can do the proper research.

Thank you!!

[Super_sally888]

You are on a big dose, but looks like it is not enough as your FT4 is way low, and your FT3 probably is also low (if it gets tested).

Doesn't matter what dose you are on, you need the dose that removes your symptoms.

Could you have absorption problems?  Have you been tested for celiac?

Also maybe they should check adrenal function.  

[roguesandy]

Make sure to get RT3 also (reverse T3) as well as the thyroid antibodies, TPO and TgAb.

Low TSH with hypo symptoms can also be that the cells are not able to signal the brain that they need more hormone, so it is not just a pituitary issue. But either way, it's not your TSH that you want to raise - that's just the "messenger" that tells the thyroid to pump out more hormone. The point is to raise your T4 and T3 until your hypo symptoms resolve.

[gimel]

What brand of T3 and T4 meds are you taking?

[Lilybsmommy]

Yep, that dosage is right, pretty crazy huh? I have hypo quite severely I have been told.

But even with this dosage, I have gained about 15 pounds in less than a month (no diet or exercise change), become quite easily irritated, and cannot think clearly or remember things like I used to... I am craving salt so badly, it is weird.

Thank you so much, I feel much better after your response. For some reason I got it stuck in my head that because my TSH and T4 were both low, it meant pituitary....

Either way, I just want this fixed so I can be normal again. We want to try for another baby but I cannot do that in good conscience until I get myself fixed....

Thank you again,
LA

[gimel]

Not sure why you are concerned that there might be a pituitary problem.  If it is because of the low TSH, even with low FT4, that's why I mentioned not to worry about the TSH.  TSH is totally inadequate as a diagnostic (at best it is only an indicator), even before taking thyroid meds.   When taking heavy dosage of thyroid meds, it is even less reliable, and frequently suppressed below the lower range limit.  For example, my TSH has been about .05 for well over 25 years while taking a full daily replacement amount of thyroid meds.

You stated that you are taking 100 mcg of T3 plus 137 mcg of T4 daily.  That would be an enormous dose.  Please double check those amounts and confirm.

Again, you really need to make sure to get tested for Free T3, along with the Free T3 and TSH.

[Lilybsmommy]

*freak not frek* :)

[Lilybsmommy]

Thank you for your comments. My meds for my compund hypo are T3 100 MCG and T4 137 MCG SR. Instead of being worried about hyper or hypo (as I already have been diagnosed with severe hypo), I am more concerned about secondary hypo... Can secondary hypo be a possibility with only these two test results? Again, I have an appointment with a specialist, but I have to wait until the end of July to get in, and it is really frustrating to me (a total control frek :)) to not know what is going on.

Thanks again,
LA

[gimel]

Not to worry about your TSH.  TSH causes no symptoms, it is just a signal from the pituitary to the thyroid glands to produce thyroid hormone.  TSH is frequently suppressed when taking thyroid meds.  That does not mean that you are hyper, unless you also have hyper symptoms due to excessive levels of the biologically active thyroid hormones, which are Free T3 and Free T4.

You are missing the most important thyroid hormone test, which is Free T3.  FT3 largely regulates metabolism and many other body functions.  Scientific studies have shown that FT3 correlated best with hypo symptoms, like those you mentioned, while FT4 and TSH correlated very poorly.  You should request testing for Free T3 along with the Free T4 and TSH.  If the doctor resists, then you should insist and not take no for an answer.  

From your FT4 test, I expect that your FT3 will also be low in its range, which is frequently is associated with being hypo.  I also expect that you need to have your meds increased.  What med are you currently taking and what dosage?

A good thyroid doctor will treat a hypo patient clinically by testing and adjusting FT3 and FT4 as necessary to relieve symptoms, without being constrained by resultant TSH levels.  Symptom relief should be all important to you, not test results.  Test results are valuable mainly during diagnosis and then afterward to track FT3 and FT4 levels as meds are revised to relieve symptoms.  You can read all about clinical treatment in the letter in this link.  It was written by a good thyroid doctor for hypo patients that he consults with from a distance.  The letter is sent to the PCP of the patient to help guide treatment.

http://hormonerestoration.com/files/ThyroidPMD.pdf

When you go back for testing, if you haven't been tested for the thyroid antibodies, TPO ab and TG ab, then that would be a good idea.  That would determine if Hashimoto's Thyroiditis is the cause for your hypothyroidism.   Also, many hypo patients find their levels of Vitamin a, D, B12, iron/ferritin, zinc, magnesium, and selenium are also low, so a good idea to have those tested as well.