Avatar universal

Low free t4, but why is my Tsh fine?

My free T4 ranges from .40 - .61 (for the past 3 years) and my tsh is always normal (1.21 - 1.7). Free T3 is also normal 3.2 -4.0). But I feel like I'm dying. And my hair has been falling out like crazy for the past year. I had really thick hair and now I am seeing thinning and scalp. I'm freaking out. The endocrinologist won't listen to me! I also have PCOS and was just medicated for rheumatoid arthritis (swollen, painful, stiff joints upon waking up daily). I've blamed the fatigue on these. And the inability to lose weight (even sticking to plan on weight watchers and exercising). I just don't want to go bald. I'll deal with the rest. My internist has done a ton of blood work and said he sees nothing except the low T4 that could account for hair loss. Iron was low, but I started supplements and hair is still coming out in handfuls. Please help. Why is my T4 so low if my Tsh is fine????
4 Responses
Avatar universal
In trying to assess a person's thyroid status the most important indicator is an evaluation for symptoms that occur more frequently with hypothyroidism than otherwise.  Your have a number of symptoms that are typical of hypothyroidism.  The next thing to evaluate is tests results for Free T4 and Free T3.  Within normal ranges, TSH has only a very weak correlation with Free T4, and a negligible correlation with symptoms.  So, TSH is useful for diagnosis only when it is at extreme levels, which your TSH is not.  In order for us to evaluate your Free T4 and Free T3 levels, please post the reference ranges shown on the lab report.

In addition, there are other variables that are important for a possible hypothyroid patient.  If you have been tested for cortisol, Vitamin D, B12 and ferritin, please post those as well.  
Most recent blood work with lab's reference range in parenthesis:
Tsh 1.338  (.35-5.5)
T4 Free .50 (.56-1.64)
T3 Free 3.2 (2.7-4.3)
Ferritin 69 ng/mL (10-232)
B-12 1465 (200-1100)
Vit D 25 hydroxy 42.19 (30-100)

However, I've been on Vitamin D, B-12, and Iron supplements daily for a couple of years now because they were all really low. I just recently started the B-12 every other day since it came back so high.
Avatar universal
It appears that the Endo is only paying attention to your TSH level, and doesn't accept that there is something called central hypothyroidism.  With central hypothyroidism, there is a dysfunction in the hypothalamus/pituitary system resulting in TSH levels that are too low to adequately stimulate the thyroid gland.  Doctors like to believe that central hypothyroidism is a rarity: however, it is rare only because it is so seldom diagnosed due to over-reliance on TSH as the sole diagnostic.  

Along with your numerous symptoms that are frequently related to hypothyroidism, your Free T4 is actually below its range.  Your Free T4 is  even worse when you understand that due to the erroneous procedure used to establish FT4 and FT3 ranges, they are  far too broad and skewed to the low end.   Your Free T3 of 3.2 is only about 31% of its range, which is too low for many people.  Your FT3 being higher in range than your FT4 is likely indicative of your body converting more T4 to T3 in an effort to maintain thyroid function as best possible.  Taken together your FT4 and FT3 are much too low, and further strong evidence for hypothyroidism.   Everyone is different, but many of us have found that to achieve symptom relief required Free T4 around mid-range, and Free T3 in the upper half of its range, and adjusted from there as needed to relieve hypo symptoms.  

You are taking care of the B12.  Your D needs to be a bit higher:  50 ng/mL at minimum.  Likewise your ferritin is too low.  Needs to be at least 100.    Free T4 and ferritin levels are very important for good hair growth.  

Most important, you need a good thyroid doctor that will diagnose and treat clinically, based on symptoms, by testing and adjusting Free T4 and Free T3 levels as needed to relieve your hypo symptoms.    In addition,  a good thyroid doctor will prescribe T3 type meds like NatureThroid, Armour Thyroid, NP Thyroid, and Cytomel, when needed to raise FT3 levels.  Based on your experience to date, I expect that you need to find a good thyroid doctor.  If you will tell us your location, perhaps a member can suggest a doctor that has been recommended by other thyroid patients.  

If you want to confirm what I have said, please click on my name and then scroll down to my Journal and read at least the one page Overview of a full paper on Diagnosis and Treatment of Hypothyroidism: A Patient's Perspective.
I believe you! I’m glad someone believes me and doesn’t make me feel like I’m crazy. But I will read anything I can on the subject! Thank you!!

Yesterday, I got an appointment with the endo and she prescribed the lowest dose (25 mcg) of levothyroxine sodium just to keep me from crying. She said I still don’t meet the classic criteria for hypothyroidism and but we can see if it helps me “feel better.” I just don’t want to have noticeable balding! I really would like to find a different doctor. I live in Mechanicsburg, PA. It is near Harrisburg. I don’t mind driving if I need to. I make my husband go to Baltimore for his neurologist because he has MS. I don’t know if there are a lot of good specialists in my area.
Avatar universal
That 25 mcg of T4 will do nothing for you.    The T3 med is not additive to your prior leves.  It will only cause TSH to go down and thus reduce the stimulation of the thyroid gland to produce thyroid med.  Since serum thyroid levels are the sum of both natural thyroid and thyroid med, only when TSH is essentially suppressed will further increases in med dosage start to raise your  FT4 and FT3 levels.  

I am sending you a PM with info.  To access, just click on your name and then from your personal page click on messages.
Avatar universal
I'm so sorry you're going through this. In reading your lab numbers, is it possible that you're actually still hypo? My TSH (EVERYONE is different) sits at .001 - .007 when I feel the best. What it took for me to realize I was being under-treated was finding a doctor who treats my symptoms (hair loss, dry skin, exhaustion, swollen feet & hands.) vs. the my numbers. I also learned that T3 and T4 should be in the upper 25% of the "normal' range to be optimal.
I'm really trying to find a doctor who will treat the symptoms. This one does not and I don't like her. It took me going in and saying "I've been telling you for a year that my hair is falling out like crazy and now I'm seeing thinning spots and scalp showing through!" for her to prescribe 25mcg of thyroid medicine. And she acted like she was just doing it to pacify me. I just don't know how to find someone who will take me seriously.
Thanks! I was able to get an appointment with a new endocrinologist, but not until September! Now I’ll just wait and hope she gets to the bottom of this! I also changed my rheumatoid arthritis medicine Incase that increased the hair loss (hair loss was a side effect of the medicine, though the hair loss started long before I started that medicine).
Have an Answer?

You are reading content posted in the Thyroid Disorders Community

Top Thyroid Answerers
649848 tn?1534633700
Avatar universal
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
Chlamydia, an STI, often has no symptoms, but must be treated.
For people with Obsessive-Compulsive Disorder (OCD), the COVID-19 pandemic can be particularly challenging.
A list of national and international resources and hotlines to help connect you to needed health and medical services.
Here’s how your baby’s growing in your body each week.