Thyroid UK
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Blood Test Results

Hello everyone,

This is my first time posting. I've had an underactive thyroid for about 10 years now (can't remember precisely when I was diagnosed as the GP swept it under the carpet as something that was easily dealt with. Ho hum). I take 100 mcg levothyroxine daily. My dose was increased from 75mcg just over a year ago.

Last week I had some blood tests taken and I'd be grateful for your help in interpreting these. The GP feels all is normal but I don't feel normal. He is however referring me to a rheumatologist as he recognises that I'm not making up the worse than normal fatigue that I'm experiencing. Of course it may take some time for this to happen.

Results are:

TSH- 2.15 mIU/L (0.4 - 5.5)

Free T4 - 20.1 pmol/L (10.3 -24.5)

B12 - 500ng/L (197-771)

Vitamin D - 72.4 nmol/L (50-120)

Iron - 32.6 umol (5.8 - 34.5)

Ferritin - 162.3 ug/L (13.0 - 150.0)

In April of this year I started suffering with tinnitus which I now understand can be thyroid related. I had a CT scan that showed there was no middle ear reason for this.

Thank you very much for your help

7 Replies

There's no such thing as 'normal', where thyroid is concerned, because we are all individuals, and have different needs. What your GP means is that they are all in-range. But, that's not good enough. Your TSH is too high for someone on thyroid hormone replacement, which more than likely means that your FT3 is too low. And it's low T3 that causes symptoms, not the TSH or the FT4. You do need an increase in dose.

Your ferritin is too high, so you could have some inflammation. Your doctor ought to investigate that. Your B12 and vit D could be higher - especially the vit D. Might be a good idea to supplement that a bit.

Tinnitus can be due to low thyroid, but can also be due to low nutrients. Try taking some magnesium, that could help. You're probably low on magnesium, most people are. :)


Thank you greygoose - really appreciate your advice


You're welcome. :)

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Welcome to the forum, Mazzhak.

The goal of Levothyroxine is to restore the patient to euthyroid status. For most patients that will be when TSH is 1.0 or lower with FT4 in the upper range. FT4 needs to be in the upper range in order that sufficient T3 is converted. Your FT4 is quite good but there is scope to increase dose to raise it to see whether symptoms improve.

Ask your GP whether thyroid peroxidase antibodies were ever tested and, if so, post the results in a new question for advice.

Read Treatment Options in Email if you would like a copy of the Pulse article to show your GP when you request a dose increase.

Vitamin D is shy of the replete level 75-200. Most people are comfortable around 100 but will need to supplement during the winter months when ultraviolet light is too low to stimulate natural vitD. I would supplement 2,500iu vitamin D daily until April. Take vitamin D 4 hours away from Levothyroxine.

It is unlikely you have B12 deficiency with B12 500 but supplementing 1,000mcg methylcobalamin daily with a B Complex vitamin may improve fatigue and tinnitus.

Iron and ferritin are a little over range which may indicate inflammation or infection somewhere in the body. I would ask for them to be retested in 3 months.


I am not a medical professional and this information is not intended to be a substitute for medical advice from your own doctor. Please check with your personal physician before applying any of these suggestions.

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Hello Clutter

Many thanks for your reply, information and advice. I'll make another appointment with my GP and will post other results when available


Only start one supplement at a time. Then leave about 2 weeks before adding another. That way you can check any reactions good or bad.

Lots of us find we need to improve a wide range of vitamins to help the replacement Levo work. Typically vitamin D, magnesium, B complex, B12, selenium and sometimes ferritin.

Also, do you always take your thyroxine on empty stomach & nothing apart from water for at least an hour after. This improves uptake.

Recent research suggests Taking at bedtime may also help

Long research article - final conclusion paragraph below

"In conclusion, bedtime intake of levothyroxine in our study significantly improved thyroid hormone levels. This may be explained by better gastrointestinal bioavailability at night or by less uptake interference by food or medications. As shown in this study, bedtime administration is more convenient for many patients. Clinicians should inform their patients about the possibility of taking levothyroxine at bedtime. A prolonged period of bedtime levothyroxine therapy may be required for a change in QOL to occur."

Best advice is to read as much as you can. Vitamin and minerals levels are very important, but standard NHS thinking, doesn't at the moment seem to recognise this. You will see, time and time again on here lots of information and advice about importance of good levels of B12, folate, ferritin and vitamin D, low stomach acid, leaky gut and gluten connection to autoimmune Hashimoto's too.

Lastly the advice on ALL thyroid tests, (home one or on NHS) is to do early in morning, ideally before 9am. No food or drink beforehand (other than water) If you are taking Levo, then don't take it in 24 hours before (take straight after). This way your tests are always consistent, and it will show highest TSH, and as this is mainly all the medics decide dose on, best idea is to keep result as high as possible

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Dear Slow Dragon

Many thanks for the information and advice. After finding this forum through Thyroid UK a few weeks ago, I changed how I take my levo in the morning - I used to take it either directly before or after breakfast - and this week I have felt a significant difference. Until now this had been the only change that I made. I'll try taking it at night to see how that works.

In the past I didn't realise about fasting and not taking levo before blood tests but I did this for the last set and will now continue to do so.

Really appreciate your reply

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