What is the proper thyroid level for an under active thyroid ?

Hi all,

Although I'm on here for other health issues but it's a first on here.

I totally confused what the proper level is for Under active thyroid ? I was first diagnosed with this about 18ths ago give or take. My GP put me on 25mg of thyroxine. Then a few months later I was really unwell and everything was put down to my other issues, including APS (Hughes syndrome), thrombosis disorder, Vit D and folic acid, and many other things. The hospital told me that my thyroid levels was slightly raised T3.7 and to re-test in 3 weeks time. This was never done as sadly I lost my dad, then I had another PE, then I was diagnosed with thrombosis disorder. This was all within 8mths, I had and still losing my hair, feeling tired, etc, the hospital could not believe that my GP had not re-tested and said that my levels were so high. So I hadthey put me on 100mg and to re-test in 4 weeks. I'm feeling a little better but no much, still losing the hair etc. I tried to get an appointment with my GP and I could only get a telephone appointment next Tuesday, knowing that I'm wheelchair bound, lap long life of medical conditions, including so many allergies that would fill the front and back of a A4 piece of paper. I had a hospital appointment on Tuesday and they did the routine blood tests, and it still showed that my thyroid level was T5.9 and she told me that I was to be referred to a thyroid clinic. Because I was stunned that my levels was high and my other problems haven't changed, I forgot to ask "what is the normal thyroid level"? Sorry but I don't know the rest of the other numbers which I have notice that goes with the result, I just got the T5.9. Can someone help as I can't afford to lose no more hair, I always thought it was due to a new medication for my blood, and with everything else that's going on, I want a bit of life back. Although some of my health issues you get when your elderly, (sorry I don't mean to offend anyone), but with the right diet as well, because of IBS, the right medication, I want to start going out but I've not had the energy, and I went out for the first time for a month this week.

kind regards


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9 Replies

  • Sorry to hear you're so unwell Tina.

    Each lab has different ranges so the best thing to do is to ask at your surgery if they will make a copy of your results for you to take home. Ideally you want your t3 and t4 to be in the top quarter of the range and your tsh should be toward the bottom of the range, certainly under 2 and, if it makes you feel well, under 1.

    The 'best' results are the ones you have when wellness has been restored if that makes sense. If you're unwell and have hypo symptoms it's likely that something can be corrected or improved.

    A lot of people also find they're a bit short on various vitamins and minerals (b12, d, iron, folate etc) so it can be helpful to be tested for deficiencies as well.

    Hope that helps.

  • Hi,

    Thank you. I went to my APS clinic asked mt to tell my GP to refer me to the Thyroid clinic as my levels have been unstable, but my GP was not happy at all with this and said (my hair loss is due to my thyroid). But I have read and have been told that if it was Alopecia, yes it would be down to the thyroxine, but mine is the thinning of the hair, and in parts I can see it growing back, I presume it was due to the under active thyroid. She did put my thyroxine up another 25mg, and now on 125mg.

    Also my GP put me on a low dose of Vit D and Follic acid.

    Hopefully now I will get a full examination and information about under active thyroid as my GP has told me nothing, just take these tablets. Plus it being a second auto immune disorder I have.

    Thank you for replying.



  • Well to be honest if the thyroid clinic involves an endocrinologist it can be a lot of effort for nothing unless you have thyroid cancer or a very serious or complicated issue. Most endos are more conservative than gps and some people come away feeling worse than ever.

    The best thing to do is to get your mitts on a copy of your results then post them here. Then you can learn about where you are and what you can do to feel better.

  • I am wondering if you have had your Thyroid anti-bodies tested ? Anti-TPO and Anti-Tg.

    If your B12 is below 500 then it can be the cause of neurological conditions so it is important to have a level of around 1000.

    You are legally entitled to your blood test results so you can monitor your own progress. Your VitD will also be low if you are not able to go out. Hair loss can be due to low Ferritin. So all these things need testing as puncturedbicycle has mentioned.

    Am afraid GP's have little knowledge or interest in thyroid issues so it is best to keep on reading and taking control of your own health with advice from here.

    Hope you soon feel better :-)

  • Hi Marz

    Thank you for replying to my post. As you can see my messages from puncheredbicycle also MarLiz, I did go to my GP, and they don't do much, even explaining what it is etc. At least now I'll find out at the Thyroid clinic.

    Kind regards


  • Hope the Thyroid Clinic comes up trumps :-) If not seek out answers here on the forum ..... A good idea to follow the advice given re testing :-)

  • Sorry to hear you've been so poorly Tina. Your GP should have been increasing your dose at regular intervals, 25mg is only a starting dose. Usually they have you back for repeat blood testing, and then increase the dose gradually. From what you say, the hospital have put you onto a 100mg, and it will take around six weeks for your body to adjust to this change in dosage. Please ask your doctor to test your B12, ferritin, folate and VitD levels. These are often low in thyroid patients, and you need good levels in order to convert the thyroxine so it can be used by your body. A thyroid antibody test would be helpful too. You have so much going on with your health, do ask for these tests to be done and post your results on here for more advice. We aren't doctors, but fellow sufferers, who have been dealing with all this for some time.

  • Hi, MartiLiz

    Sorry, I have replied to your post above instead of here. Again thank you very much for your help.



  • If you are hypothyroid and treated sufficiently to restore normal health then you might have thyroid results along these lines :

    TSH - a maximum of about 1 (ish). An untreated or under-treated hypothyroid person would have a substantially higher TSH than this.

    Free T4 and Free T3 - roughly speaking these should be in the top third of the reference range for most treated hypothyroid people to feel well (but there are always exceptions to the general rules). An untreated or under-treated hypothyroid person would expect to have much lower levels of these.

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