Aa
Aa
A
A
A
Close
1567786 tn?1295903246

Low T4, normal TSH

My TSH levels are normal but my T4's are low.  Not sure what this means since if my pituitary glands are producing enough TSH what is happening to make my T4's low?
Doctor wants we to take a THS 3rd generation and a CBC and basic Metab panel.

I have all the symptoms of hypothyroid, depression, fatigue weight gain, joint pain, have cold hands and feet and got grey hair at a very early age as well as suffered infertility but she has not mentioned that and just told me to take these additional tests, so I am confused.
.
.  
Best Answer
Avatar universal
I think the most important information (your symptoms)  has already established that you are hypo.  The FT3 and FT4 tests will further confirm that, by their being in the lower part of their reference ranges.  These tests then further useful as markers to show your progress as you start taking thyroid meds and progress to symptom relief.
72 Responses
Sort by: Helpful Oldest Newest
Avatar universal
What is the reference range for the Free T4, as shown on the lab report?  What is your thyroxine daily dosage?  Also, symptoms are even more important as an indicator of thyroid status than test results.  Please tell us about any symptoms you have.

It is unlikely that you will feel better on a low dose of T4 med.  Serum levels of T4 and T3 are the sum of both natural thyroid hormone produced by the thyroid gland and also thyroid medication.  When starting on med, the TSH level drops in response, which then reduces the stimulation of the thyroid gland, and less natural thyroid hormone is produced.  The net result is little or no change in serum levels of T4 and T3 until the medication dosage is increased enough to basically suppress the TSH to the low end of its range, or below. Then further increases in med dosage will cause the T4 and T3 levels to rise.  

With a low Free T4 level the first step is to get your med dosage gradually increased as needed to get your level up to the middle of the range.  You should also make sure they always test you for Free T3 as well as Free T4.  If your Free T3 lags behind changes in your Free T4 level, then that is an indication that your body is not adequately converting T4 to T3, and that a source of T3 should be added to your med.  From our knowledge of the NHS practices, doctors only prescribe enough T4 med to get the TSH back within range.  That typically leaves patients under medicated and symptomatic.  A good thyroid doctor will treat a hypo patient clinically by testing and adjusting  Free T4 and Free T3 as needed to relieve symptoms, without being constrained by resultant TSH levels.  Symptom relief should be all important, not just test results, and especially not TSH results.  You can get some good info from this link written by a good thyroid doctor.

http://www.hormonerestoration.com/Thyroid.html

Since hypo patients are so frequently low in the ranges for Vitamin D, B12 and ferritin, I highly recommend getting those tested as well, and supplement as needed to optimize.  D should be about 55, B12 in the upper end of its range, and ferritin should be about 70.

I also want to impress on you just how difficult it is for UK patients to get the necessary testing and treatment for hypothyroidism.  One of our members who, after visits to many doctors, was finally successful described it as follows,  "What I have learned from my experience is that you have to go to the Dr's office and TELL THEM WHAT YOU WANT and to go backed up with knowledge.  You have to tell them that you have done your reading and looked into your condition and care about the long-term treatment of your health and thyroid.  If you fight for what you want, you will eventually find someone that is happy to go along with your wishes.  But we all have to take charge of our own health, right?"

Please let us know how it goes for you and we will be glad to help interpret future test results and advise further.  
Helpful - 1
1 Comments
Excellent response. Thank you.
Avatar universal
Thank you so much! I'm going to email my doctor tonight. I always feel like I'm going to "offend" him if I question things and request more tests. But, having said that, I would have never known I was hypo without demanding tests to begin with. The levothyroxine has helped tremendously with anxiety, depression and panic attacks but physically, I still feel "off". Thanks again and I'll post new results as you mentioned above.
Helpful - 1
Avatar universal
What doctors consider as normal TSH depends on the reference range they use.  The old range was .5 - 5.0.   Over 8 years ago the AACE recommended that the range should be changed to .3 - 3.0.  Unfortunately most labs and doctors have yet to adopt the new range.  

More importantly TSH is a pituitary hormone that is affected by so many variables that it is inadequate as a diagnostic.  At best it is an indicator, to be considered along with more important indicators  such as symptoms, and also the levels of the biologically active thyroid hormones, which are free T3 and free T4 (note these are not the same as total T3 and total T4).

FT3 is the most important because it largely regulates metabolism and many other body functions.  Studies have also shown that FT3 correlated best with hypo symptoms, while FT4 and TSH did not correlate very well at all.  So it is important that you be tested for both FT3 and FT4.  If the doctor resists, you should insist on it and not take no for an answer.  Remember that you are the customer.  

As far as why your T4's are low, I'd like to have you post the actual test result and reference range, please.   Also TSH please.  

I have  known of patients with pituitary issues that were somewhat similar, where the TSH was actually on the lower end of the range, so of course their FT4 and FT3 were low, resulting in hypo symptoms.  

So let's start with that.  There are a lot of  dedicated members here who will also be glad to provide you the benefit of their knowledge and experience.
Helpful - 1
1 Comments
Help to understand?  Endo says I'm fine, don't feel fine
T4 - 6.1 (Ref. Range 4.6-12.0
FT4 - .79 (Ref. Range .93-1.70)
T3 - 153.5 (Ref. Range 80.-200.)
FT3 - 3.51 (Ref. Range  2.00-4.40)
TSH - 1.410 (Ref. Range .270-4.200)
Avatar universal
Many thanks - wI'll try and digest what you have said and research into it a bit more!
Helpful - 0
Avatar universal
Hi have been reading about thyroid results. I have just had test - result
free t4 10.8  pmol/ L - low
TSH 5.15 mIU/L - high
I was put on low dose of thyroxine but stopped as it didn't really make me feel any better - I was told a while ago by a private doctor that the level of T3 was low in my blood but in the UK GP's don't measure T3 so not sure if I should have had medication to increase T3 instead of T4?
Helpful - 0
649848 tn?1534633700
COMMUNITY LEADER
What is the reference range for your T4 and is that Free T4 or Total T4?  They aren't the same tests.  
Helpful - 0
Avatar universal
my TSH is 2.79 and T4 is .78
what it means? should i take med ?

Helpful - 0
Avatar universal
Free T4. Range 0.8-1.7 ng/dl)
12/1/15 - 1.0
1/8/16 - 1.0

T3 Total (Range 50-170 ng/dl)
12/1/15 - 85
1/8/16 - 87

He never did do the Free T3
Helpful - 0
1 Comments
The biologically active thyroid hormones are Free T4 and Free T3.  You should make sure they test both every time you go for tests.  If they resist, just insist and don't take  no for an answer.  

Why did the numbers change from your first post to the second?

Even though your TSH is within range, more importantly, at 1.0 your Free T4 is too low in the range.  It should be at mid-range at minimum, which would be at least 1.25.  If your Free T3 is comparable to your Total T3, relative to its range, then your T3 is also too low in the range.  Free T3 is best in the upper part of its range, as needed to relieve hypo symptoms.  A good thyroid doctor will treat a hypo patient clinically by testing and adjusting Free T4 and Free T3 levels as needed to relieve symptoms without being constrained by resultant TSH levels.  Symptom relief should be all important, not just test results.  

Even if Free T4 and Free T3 are optimal, low Vitamin D, B12 and ferritin can also cause symptoms that mimic hypothyroidism.  Also, low D and low ferritin can adversely affect metabolism of thyroid hormone.   D should be about 55-60, B12 in the upper end of its range, and ferritin should be about 70 minimum.  If not tested for those you need to do so and then supplement as needed to optimize.  
Avatar universal
My T3 is 69.70 and T4 is 4.74 while TSH 3rd gen is 2.6 .. what do these figures indicate ? I feel the fatigue and cold hand and feet.
Helpful - 0
1 Comments
What are the reference ranges for the T4 and T3, as shown on the lab report?  
Avatar universal
The jeopardy with your new lab results is that if the doctor has the "Immaculate TSH Belief' and only really pays attention to TSH, then you might be told that all is well and no further increase in meds is required.  Not so.   Your Free T4 is below level we consider minimum which would be 1.25 (middle of the range).  You weren't even tested for Free T3 which is the most active thyroid hormone.  FT4 and FT3 should be tested every time you go in for tests.  If your Free T3 is as low in its range as your Total T3, that will be very indicative of being hypothyroid.  

A good thyroid doctor will treat a hypo patient by testing and adjusting Free T4 and Free T3 as needed to relieve symptoms, without being constrained by resultant TSH levels.  Symptom relief should be all important, not just test results, and especially not TSH.  I say that because hypo patient taking adequate thyroid medication often find that their TSH becomes suppressed, and the doctor reacts by reducing meds.  That is not correct unless the patient is  having hyper symptoms due to excessive levels of Free T4 and Free T3.  So your med dosage is only a starter dose and you need to be gradually increased as needed to relieve symptoms.  

Also hypo patients are frequently too low in the ranges for Vitamin D, B12 and ferritin.  Low levels can cause symptoms.  Low D or low ferritin can also adversely affect metabolism of thyroid hormone.  D should be about 55-60. B12 in the upper end of its range, and ferritin about 70 minimum.  After testing you can supplement as needed to optimize.  
Helpful - 0
1 Comments
You were right, Gimel, about having a doctor that really just looks at the lab ranges and dismisses you. Due to increased symptoms, I requested additional testing as you recommended. He didn't want to do them and basically told me he didn't think they were necessary but he would order them and that there was no difference between Levothyroxine and brand-name medications.  Wow.

TSH (Range 0.10-5.50 uiv/ml)
12/1/15 - 1.7
1/8/16 - 2.7

Free T4 (Range 0.8-1.7 ng/dl)
12/1/15 - 1.0
1/8/16 - 1.0

T3 Total (Range 50-170 ng/dl)
12/1/15 - 85
1/8/16 - 87

B-12 (Range }=200 pg/ml)
1/8/16 - 572 pg/ml

Ferritin (Range 22-291 ng/ml)
1/8/16 - 107 ng/ml

Calcium (Range 8.5-10.3 mg/dl)
1/8/16 - 9.8 mg/dl

Magnesium (Range 1.7-2.3 mg/dl)
1/8/16 - 2.0 mg/dl

He still didn't order the Free T3 and I specifically requested it. I'm not happy at all with his dismissive attitude. Actually asked me if I wanted antidepressants.   Lol.

Why is my TSH going back up??
Avatar universal
Oops, meant to do that.

TSH 1.71 uIU/mL (Range 0.10 - 5.50)
T3 Total  85 ng/dL (Range 50 - 170 ng/dL)
Free T4 is 1.0 ng/dL (Range 0.8 - 1.7 ng/dL)
Cortisol 8:00 AM 23.7 ug/dL (Range 8.0 - 25.0 ug/dL)

Im glad my TSH is down but I feel my T4 and T3 are on the low end of ranges. Doing a suppressed Cortisol test next week.
Helpful - 0
Avatar universal
Please post the reference ranges for the Free T4, Total T3 and cortisol tests, as shown on the lab report.  The reason I ask is that results and associated ranges will vary from lab to lab so results should always be compared to ranges from same lab.
Helpful - 0
Avatar universal
Started on .25 Levo 2 months ago. After 2 years of being told my symptoms were menopause and offering antidepressant and counseling, I finally demanded more tests.  TSH was 4.5 and FREE T4 was 1.0.  Was told it was borderline hypothyroid and began treatment. Also Cortisol at 8:00 am was 23.7 ug/dl, which doctor said was elevated.  Most recent labs are TSH is 1.8, Free T4 is 1.0 and Total T3 is 80. These are Kaiser labs. Wondering if my T4 and T3 are still low. I feel better on meds, but still off, horrible sleep, retaining water, fat face, weight gain. I'm 5'4 and 149 lbs. I've gained 25 lbs in one year before diagnosis.
Helpful - 0
Avatar universal

TSH                         2.330  uIU/mL         0.450 - 4.500 01
Thyroxine (T4)          4.2   Low     ug/dL      4.5 - 12.0 01
T3 Uptake       27 %                                     24 - 39 01
Triiodothyronine (T3)   81 ng/dL                71 - 180 01
Triiodothyronine,Free,Serum 2.7  pg/mL      2.0 - 4.4 01
T4,Free(Direct)       0.78 Low ng/dL           0.82 - 1.77 01
Reverse T3, Serum        11.0        ng/dL     9.2 - 24.1 01



Thanks!

STan
Helpful - 0
Avatar universal
Just because your lab results fall within the so-called "normal" ranges does not mean they are adequate for you.  The ranges are faulty, due to the erroneous assumptions used in establishing them.  I think you will get a better understanding of this when you read this, which was written by a good thyroid doctor.  In the words of a good thyroid doctor,

"The free T3 is not as helpful in untreated persons as the free T4 because in the light of a rather low FT4 the body will convert more T4 to T3 to maintain thyroid effect as well as is possible. So the person with a rather low FT4 and high-in-range FT3 may still be hypothyroid. However, if the FT4 is below 1.3 and the FT3 is also rather low, say below 3.4 (range 2 to 4.4 at LabCorp) then its likely that hypothyroidism is the cause of a person's symptoms."

Also, your doctor is no doubt confused by the fact that your TSH is low in its range, which with your FT4 and FT3 would be consistent with central hypothyroidism.  Central hypothyroidism is associated with a dysfunction in the hypothalamus/pituitary system that results in inadequate TSH to properly stimulate the thyroid gland.  

A good thyroid doctor will treat a hypo patient clinically by testing and adjusting Free T4 and Free T3 as necessary to relieve symptoms, without being constrained by resultant TSH levels.  Symptom relief should be all important, not just test results, and especially not TSH results.  

Hypo patients are also frequently too low in the ranges for Vitamin D, B12 and ferritin.  All three are important.  Low levels can cause symptoms that mimic hypothyroidism and also adversely affect metabolism of thyroid hormone.  D should be about 55-60, B12 in the upper end of its range, and ferritin should be about 70 minimum.  So you should get those tested and supplement as needed to optimize.
Helpful - 0
Avatar universal
I am at a loss. I feel horrible but my drs keep telling me i'm fine. They have sent me to a psychiatrist for depression and ADD, Really?! I am 46! I have been going now for 3 years and they just keep prescribing different scripts. Nothing is changing the way I feel. I have been asking them to check my thyroid all this time and always the same, in range. So now I go to my pc dr. and he says my thyroid is enlarged so he sends me for an ultrasound. It comes back ok. So I asked why it is swollen then? I got the I don't know answer. Again really?!
My thyroid test results are
Free T4 .98      Range.80-1.80 ng/dl
Free T3 2.9      Range 2.3-4.2
TPO  47         Range <60 u/ml
TSH  1.02       Range .30-5.00 ulu/ml
Help!!
Helpful - 0
Avatar universal
I just sent you a PM with info.  To access, just click on your name and then from your personal page click on messages.  
Helpful - 0
Avatar universal
Thanks again!

It looks like they are only measuring free T4 and total T3 (as well as the other useless tests for TSH, etc. as you mentioned).  The PCP is hesitant on making any changes, even when my free T4 is at an all time low (0.8).  Still waiting on the total T3 but sounds like that won't provide any useful info.

I actually was impressed with the PCP because she said we need to watch prolactin, which could indicate a pituitary problem.  The prolactin levels have decreased into the normal levels with this test.

B12 (385) and D (28) are low and I need to supplement more than I am doing.  Ferritin is good at 92.

Can't get an appointment with my endo until end of August. In any case, I'll have the PCP forward over my recent test results in the hopes that he will at least prescribe something.

I live in Chicago - any suggestions?

Thank you again!
Helpful - 0
Avatar universal
Well, T3 uptake and Free Thyroxine Index are outdated tests.  I can't tell if your T4 and T3 tests were for Total T4 and Total T3 or Free T4 and Free T3.  You should insist on the Frees each time they test you.  Not sure what you mean by the TP+T3 test.  If your PCP did those tests I suspect that he is also out of date when it comes to thyroid testing.  

Be sure to get tested for Vitamin D, B12 and ferritin and supplement as needed.  

Reverse T3 is the mirror image of T3, but RT3 is biologically inactive.  T4 is converted to both T3 and Reverse T3 as a normal process.  Under unusual conditions too much Reverse T3 is produced and that can offset the effect of Free T3.  Reverse T3 dominance is not a frequent problem, but I just think it would be a good idea to check yours to verify it is okay.  

As for finding good thyroid doctors, we are always on the lookout for those.  We keep lists of those we find, and provide the names to members, if there is one in the area.  If the Endo is not willing to treat clinically, then we will try to give you recommended doctors in your area.  
Helpful - 0
Avatar universal
I do believe my doc will do testing and treating based on my input - but we'll find out!

His tests were very broad last time, including thyroid, hormones,vitamins, cholesterol, blood counts, etc.

For the thyroid, he tested:
TP+T3:  thyroxine (T4); T3 Uptake; Free thyroxine index shown as a percentage; triiodothyronine (T3);
Throxine (T4) Free
TSH

Everything was fairly low, and he raised my dose of synthroid (T4).

What is Reverse T3?

How do you find a doctor who will treat your symptoms and try to get optimal results?  I'ts not like they state that in their bios.  This endo is the best one I've seen - and I've been to three.

Thanks again!

Susan
Helpful - 0
Avatar universal
It isn't just PCP's that don't treat clinically.  Endos seem to be even more rigid about using "Reference Range Endocrinology" by which they will tell you that a thyroid test that falls anywhere within the range is adequate.  That is very wrong.  The ranges are far too broad to be functional across their entire breadth for everyone.  

The ranges for Free T4 and Free T3 are based on all test data at a given lab, with the only exclusions being patients that have a TSH that exceeds its range limit.  Of course there are lots of hypothyroid patients that have TSH within the range, especially those with central hypothyroidism.  This means that there are lots of hypothyroid patients' data included in the data bases for FT4 and FT3.  So the calculated ranges are far too broad.  If  based only on healthy adults with no known thyroid pathology these ranges would be more like the upper half of the current ranges.  

That is why we say that a good thyroid doctor will treat a hypo patient clinically by testing and adjusting Free T4 and Free T3 as necessary to relieve symptoms, without being constrained by resultant TSH levels.  Symptom relief should be all important, not just test results.  Many members, myself included, have found that relief from hypo symptoms required Free T4 at the middle of its range, at minimum, and Free T3 in the upper third of its range, or as necessary to relieve symptoms.  Your Free t4 is at rock bottom of the range, and I expect your Free T3 to be similar.  

Is the test result you are expecting for Free T3, or Total T3?  Will your Endo always test you for both Free T4 and Free T3?  If not, you should insist on both.  In fact I would even ask for Reverse T3 just to check that also.  Also, will your Endo be willing to treat clinically as I described above?  If not, then you are going to have to find a good thyroid doctor that will do so.  
Helpful - 0
Avatar universal
Thank you for your response!  

Not diagnosed with Hashimotos - just got an annual checkup at age 40 and they found that 'thyroid was low' (I don't have the specifics as that was 15 years ago), as well as cholesterol was high - at the time I had absolutely no symptoms. Getting thyroid in range helped lower my cholesterol.  At the time I was skinny as a whip, exercised frequently and ate cleanly.   My mom also had thyroid issues.  Since then my weight has increased by over 40 pounds, which is a lot for someone 5 ft 4.  I am still relatively active and eat a healthy diet.

We are waiting on the T3 result according to my PCP (not sure why other results came back quicker?)

My endo doc tests everything fully and is really great.   Excellent points about D and B12 - first time I've heard about Ferritin.   I have had low D (34.8) in the past and am taking supplements (5000 IU), although during the summer I usually just take them included in my Nordic Natural Fish Oil (1000 IU) and my multivitamin (1600 IU) and get some sun. Same thing with B12: in range but needs to be higher (currently 385).  Ferritin also normal at 78, so good.  Last T3 result was 90, which is at the lower end of the range, but the endo didn't do anything.

I'm calling the endo to schedule an appointment tomorrow.  He will do the full spectrum of tests and probably address the low T4 and possibly T3.  The PCP felt that T4 was OK even though it was almost at the bottom end of the range.  Is that because TSH was mid range and PCPs don't really bother with trying to treat symptoms?

You are a blessing to this thread!  Hope you know that!  
Helpful - 0
Avatar universal
When you were first diagnosed as being hypothyroid, was the cause identified?  I'm wondering if it was Hashimoto's Thyroiditis?  That would be consistent with the need for increasing dosage of Synthroid.

Also, have you ever been tested for Free T3 along with the Free T4?  Free T3 largely regulates metabolism and many othe body functions.  Scientific studies have shown Free T3 to correlate best with hypo symptoms, while Free T4 and TSH did not correlate.  With your current low Free T4 level, and you taking a T4 med I expect that you will find your Free T3 to be very low also.

I like whatever thyroid medication fulfills your needs.  If the T4 is being adequately converted to T3, then that is certainly the most convenient medication to take, since it can be done once a day and is slow acting.  If your body does not convert T4 to T3 adequately which is often the case, then a source of T3 is necessary.  You could just add T3 to your T4 med for that.  Or you could switch to an NDT type like Armour or Nature-throid.  I am using Armour and Cytomel.  

Also be aware that hypo patients are often too low in the ranges for Vitamin D, B12 and ferritin.  If not tested for those, you should do so.  D needs to be about 55-60, B12 in the upper part of its range, and ferritin should be 70 minimum.  Deficiency in any of the 3 can cause symptoms, and low D and ferritin can also adversely affect metabolism of thyroid hormone.
Helpful - 0
Avatar universal
You are very knowledgeable and I thank you for your responsiveness to the community.   I am also happy to hear you recommend that we demand proper tests and treatments for our doctors.  I am in Chicago and have a great endocrinologist who totally follows your line of thought with testing and treatment, as well as having a phenomenal bedside manner and plenty of time for his patients.   I have been on synthroid for 15 years, and the dose continues to climb.

I recently went in to my primary care physician for some digestive issues.  She is in the same system as my endo, and she said, when was the last time you had your thyroid tested?  It has been almost a year (shame on me!).  She said, let's do a quick checkup while you are here.  She did not do a full test - I will make an appt. with my endo for that. The results are:  free T4 of .8; TSH of 2.13; and prolactin of 23.5 (it had been higher last time at 30+).  She talked to me about pituitary function and said we might want to look at that down the road if prolactin continued to rise.  I'm a 55 year old female that is in menopause.

I'm waiting to hear back from my PCP - but as we are going into a holiday weekend, probably won't until next week.

I clicked on the links you have shared, and I'm wondering what you think about Amour or Nature-throid?  Should I ask my doctors to switch me to this?  I have gained over 35 pounds in the last 5 years, and I exercise and maintain a good diet.

Thanks again for your good advice!

Susan
Helpful - 0
Have an Answer?

You are reading content posted in the Thyroid Disorders Community

Top Thyroid Answerers
649848 tn?1534633700
FL
Avatar universal
MI
1756321 tn?1547095325
Queensland, Australia
Learn About Top Answerers
Didn't find the answer you were looking for?
Ask a question
Popular Resources
We tapped the CDC for information on what you need to know about radiation exposure
Endocrinologist Mark Lupo, MD, answers 10 questions about thyroid disorders and how to treat them
A list of national and international resources and hotlines to help connect you to needed health and medical services.
Herpes sores blister, then burst, scab and heal.
Herpes spreads by oral, vaginal and anal sex.
STIs are the most common cause of genital sores.