Thyroid UK
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I would like help to understand my blood tests results with the relevance to the dose change of Levothyroxine & the changes of the symptoms

I am a 66 years old woman and had a total Thyroidectomy in July and am currently taking 75 mcg of Levrothyroxine. This is the first month of taking a reduction from 100mcg to 75mcg and am being monitored by my GP each month until I am stablised. I have been reading a lot of information on this site and Thyroid UK site as recommended, but still feel confused about the relationship between the THS and T4 in the blood test results and what it is actually indicating.

The latest blood test results taken at the beginning of October show: TSH - 0.11 mU/L within the range (0.35-4.94) and T4 (thryoxine free) - 14.50 ng/L within the range (7.00-14.80). My GP said that the T4 was too much and the TSH was not enough and the trick is to get the balance right. I am not sure what the "right balance" is? I know that it is not right at the moment.

With the change, I feel a little better overall but I still do not feel right - ie the vertigo has lessened considerably. This has much improved as the vertigo was happening much of the day and at night when sitting, laying down and walking was a nightmare as it felt as if I was going to pass out. Now, most of the day the vertigo is gone but I still do not feel able to drive as occasionally if I do turn my head quickly by brain spins. The numbness in my right leg has virtually disappeared too.

However, I seem to be swinging from having loads of energy, feeling so good, positive attitude, clearer thinking, no aches or pains, but being able to sleep very little and the least little noise disturbs me. The other extreme is the complete opposite and horrible. The shift can happen very swiftly and without warning from one state to the other, noticing that shift from positive to negative can happen swiftly if I am stressed by something. The two extreme states are difficult to cope with.

I do have confidence in my doctor but I would like to have a little more understanding of what the results mean so that I can ask any relevant questions when I have the next blood test at the beginning of next week.

Many thanks

ps. I must add that the result ranges are that of the french medical system and may be different to that of the UK ranges.

5 Replies

.....Hi White_Mist - yes the ranges are a little different in each lab. Your T4 upper range does seem low compared with the UK and here in Crete. As you do not feel well and still have symptoms it could be that you have not yet found your optimal dose. You didn't mention why you had your thyroid removed - were you overactive ? As is often said on this forum - it is how you feel that is important - and that the blood test is just a guide. Most people feel better with a TSH of 1 or under and the FT4 needs to be at the top of the range.

You do not have a FT3 result - as that is the active hormone it would be helpful to have that figure - it would also indicate if you are converting your T4 tablet into T3. If you are not converting that could make you feel poorly - as the much needed T3 is not getting into the cells - and the T4 could also be backing up in the blood . How did you feel on the 100mcg ? The right balance your Doc mentions is the right amount for you - it is very personal and one size fits all is not a good barometer. How is your B12 Ferritin Iron Folates and VitD - all these need to he high in the range for optimal conversion and well being.....

I still have my thyroid so I do not have good knowledge of the situation that you are in. Am sure there will soon be lots of people coming along to help you. I do hope that soon the good periods get longer and you will enjoy good health .....

1 like

Thanks for your explanations Marz, I have a better understanding now I had my thyroid removed because of having multiple nodules -1 very large one, 1 not so large (both active) and several smaller ones (not active). The two larger ones had been actively growing during the last year and the control scan showed that the very large one had descended into my thorax. Thankfully the surgeon was able to remove everything without cutting into my sternum. I came out of hospital with 150mcg with which I persevered for 2 weeks but the symptoms were so extreme that my GP changed the dose to 100mcg immediately without blood tests, which I took for 6 weeks (test results as above). The 100mcg greatly reduced the side effects to a tolerable level compared with the previous dose but am still not really able to function properly.

My GP has not asked yet for any T3 or vitamin tests to be done but suggested that I take Berroca. I do have a history of being anaemic at various times due to being unable to process iron properly. An enlightened British GP explained that my body does not absorb Vitamin C very well so it is necessary for me to take high doses of Vitamin C for my body to convert iron (really heavy blood loss and long periods and being very anaemic during pregnancy with iron injections making no difference ). I have been self-medicated with Vitamin D12, Vitamin D3 and a general multivitamin (but not iron) for a number of years. Having read advice on this forum, recently decided to stop taking all the vitamins/minerals to give a better picture of what my body is actually doing on its own - then ask my GP FT3 test and for a vitamin/ mineral test to be carried out next month as part of the control tests.

My French GP is not difficult and will listen to well put forward opinions. I had originally asked for a thyroid test as part of an elimination process, as symptoms that I was displaying last year were getting worse but could be explained by a number of conditions. He did not mess about and ordered a scintigraphy which showed the multiple nodules at that time. The radiologist who carried out the scintigraphy explained that I most probably had always had thyroid problems which would have started, in my case at puberty, and advised that I should have an echography each year as a control. Most radiologists in France are diagnostic radiologists and are recognised as doctors in their own right.


....thank you for your reply. You seem to have your finger on the button and making good progress with lots of things in place and a plan for the future ! Great news. We too have good radiographers who are doctors - who talk you through the process as if you were having a coffee and we leave with the pictures and a report within minutes of the appointment. So civilised....and no one appearing superior to the next one ! Sending the results to the GP as they do in the UK is so outdated and time consuming - then they get lost - further GP appointments have to be made and they are already overstretched !! No common sense as far as I can see.

Its good to hear you are receiving good treatment with an understanding doctor - through what must have been a difficult time for you. Take good care and I will look out for your posts....


Are your calcium levels ok? I had have had a total thyroidectomy and suffered many of the symptoms you mention, particularly the noise sensitivity when my calcium levels were swinging below range.


Thank you for your reply Debjs. My GP has put me on 1000 mg of calcium per day. Unsure about how the calcium helps or what it does though. I found that the numbness and pins and needles in one leg and foot have been almost eliminated – that was most odd and quite worrying.

The advice on this forum suggested that calcium interferes with the efficiency of levothyroxine, so I switched taking it from lunchtime (advised by the pharmacy) to the evening. There seems to be a difference but it would be very hard to say exactly what it is.


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