If free T3 and free T4 are both very low in range, is levo necessary regardless of TSH, if there are hypo symptoms such as tiredness and weight gain? If TSH is out of range, should levo be taken irrespective of free T3 and free T4 results?
Does low in range T3 and low in range T4 cause symptoms in most people?
What should TSH be to feel well and to be free of all hypo symptoms? How much does this vary between different people?
I'm trying to find out if my daughter should self medicate as she is getting no help from her gp and her health is deteriorating rapidly.
Any help or advice is really appreciated.
Written by
dizzy864
To view profiles and participate in discussions please or .
I have just seen your post from yesterday, I am going to answer that first.
I may be a while, it's my father-in-law's funeral today which I am attending "remotely" and the webcast is due to start in about 20 minutes, but I will reply.
TSH is a hormone produced in the pituitary gland in your head. It goes into the bloodstream and stimulates the thyroid gland to produce T4 and some T3. The T4 and T3 now enter the bloodstream in their turn. Some of the T4 is converted to T3 there. So the T3 comes from both thyroid (directly) and T3 produced by the body from T4. They then influence cells in your body to give you a normal healthy state of life (T3 doing the most work). If the thyroid starts to fail, then the gland tries to compensate for its falling activity by maintaining its T3 production. For that it needs more TSH to stimulate the gland in this way. Therefore for a long time, the combination of body and thyroid-made T3 keeps fairly constant. But T4 production has gone down because of the gland failure. And TSH has risen in an attempt to maintain bodily health as well as possible. When the thyroid completely fails then the only T3 that is made comes from the body's conversion of T4. This is the state of hypothyroidism, when TSH is high and FT4 low, and FT3 somewhat low. The TSH range for healthy people is about 0.5-4.5 units. For patients under therapy especially those with no thyroid, the TSH range is lower about 0.05-1.5.
TSH is a pituitary hormone. When the pituitary senses that levels of T3 and T4 are low in the blood, it produces TSH - Thyroid Stimulating Hormone - to stimulate the thyroid to produce more thyroid hormone.
FT4 and FT3 are the names of the tests to tell how much thyroid hormone you have available for use by the body.
If free T3 and free T4 are both very low in range, is levo necessary regardless of TSH,
Yes. There's a condition called Central Hypo, where - for whatever reason, and I won't go into that here - the pituitary does not produce adequate amounts of TSH. So, the thyroid is not stimulated, the T4 and T3 levels drop, but the TSH remains low.
This is reported to be a rare condition, so a lot of GPs have never heard of it, and don't understand how it works. And, so, it goes undiagnosed in a lot of people, and therefore becomes even rarer!
If TSH is out of range, should levo be taken irrespective of free T3 and free T4 results?
Yes, because if FT4/3 are at euthyroid levels, it is because of the TSH. If it is obvious that it takes a lot of TSH to force the thyroid to make euthyroid levels of T4 and T3, it means the thyroid is struggling, and the situation cannot last. Eventually, the T4/3 levels will drop further, and TSH will rise even more but the thyroid will be unable to respond. That is hypothyroidism.
Does low in range T3 and low in range T4 cause symptoms in most people?
Low T3 causes symptoms. T3 is the active hormone, T4 is basically a storage hormone - it's not really sure if it does anything else.
There are over 300 symptoms of hypothyroidism. The most well-known are fatigue, wieght-gain, hair-loss, depression, low temperatures and feeling cold. But, not everyone has those particular symptoms, and they therefore believe they are symptom-free. But, they do have other, more obscure symptoms, like high blood pressure, failing sense of hearing, scalloped tongue, etc. Everyone has their own set of symptoms, and you don't have to have all 300 to qualify. But, I would be very surprised if someone with low levels of thyroid hormones had no symptoms at all.
What should TSH be to feel well and to be free of all hypo symptoms? How much does this vary between different people?
It's not really about the TSH - although doctors think it is. The TSH itself doesn't cause symptoms of any sort. It's about the FT3, and when the FT3 is high enough to get rid of most people's symptoms, the TSH can often be very low/suppressed. But, if you're one of those people that is happy with lower levels of FT3, the TSH could be good for you at about 1 - or even 2. The TSH follows the FT3. as the FT3 rises, the TSH drops.
Quite how much this varies from person to person is an unknown quantity, there are so many variable. We're all individuals and should be treated as such - something doctors definitely don't do!
I'm trying to find out if my daughter should self medicate as she is getting no help from her gp and her health is deteriorating rapidly.
Any help or advice is really appreciated.
Really difficult to give your daughter any advice without seeing full thyroid labs:
TSH
FT4
FT3
TPO antibodies
Tg antibodies
vit D
vit B12
folate
ferritin
The NHS usually won't do all that, so I would say her first step to good health would be to get these tests done privately. Details here:
Sorry, just seen your post from yesterday - should have looked first before answering! You've now got an excellent reply from Susie, so I can't add to that. Just ignore the bottom bit of my post!
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
Lower T4,T3,FT3,FT4,TSH after taking Levo
Free T3 levels compared to Free T4
Low TSH High T3 Normal T4 Total Thyroidectomy
Feedback loop TSH/T4/T3
