Blood test result: help! : This is the first time... - Thyroid UK

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Blood test result: help!


This is the first time I’ve requested my blood tests results and I have no idea what I’m looking at.

I’m in 50mg of Levothyroxine.

Serum TSH level - 4 mIU/L 0.30-4.80 mIU/L

Serum free T4 level - 9.5 pmo/L. 7.70-20.60 pmol/L

My doctors have advised this is normal.

Could anyone advised me whether this makes sense?

23 Replies

That's just the ranges, what were your actual results 😊

CurteisS in reply to fibrolinda

Oh I see haha. TSH is 4 and T4 is 9.5

SeasideSusieAdministrator in reply to CurteisS

You are undermedicated with those results. Did you have an increase in dose after your GP saw those results?

The aim of a treated hypo patient generally is for TSH to be 1 or lower with FT4 and FT3 in the upper part of their ranges if that is where you feel well.

If you didn't behave an increase back then you need an increase in your dose of Levo 25mcg now, retest in 6-8 weeks, repeat until your levels are where they need to be for you to feel well.

No I was on 50mg when I had those results and the doctor said I don’t have to increase. I know something isn’t right cause I’m still so tired all the time and finding it impossible to lose weight. How would I go about trying to increase my dose?

SeasideSusieAdministrator in reply to CurteisS

How would I go about trying to increase my dose?

Here is a list of signs/symptoms of hypothyroidism:

Tick off any that apply. Show it to your doctor and emphasise that you are still suffering from symptoms of underactive thyroid which, if you were optimally medicated, should be alleviated.

You can use the following information to support your request for an increase in dose:

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine (the magazine for doctors):

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l. In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l. Most patients will feel well in that circumstance. But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l. This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l).*"

*He recently confirmed, during a public meeting, that this applies to Free T3 as well as Total T3.

You can obtain a copy of the article by emailing Dionne at

print it and highlight question 6 to show your doctor.

Serum TSH level - 4 mIU/L 0.30-4.80 mIU/L

Serum free T4 level - 9.5 pmo/L. 7.70-20.60 pmol/L

Point out that your TSH is very close to the top of the range and that your FT4 is a measly 13.95% through range, a far cry from what Dr Toft mentions.

[calculator here:]

You can also refer to NHS Leeds Teaching Hospitals who say

Scroll down to the box

Thyroxine Replacement Therapy in Primary Hypothyroidism

TSH Level .................. This Indicates

0.2 - 2.0 miu/L .......... Sufficient Replacement

> 2.0 miu/L ............ Likely under Replacement

If necessary, take someone with you to the consultation who can advocate for you if you find it difficult to get your point across yourself. It's often the case that when there is another person in the room, particularly a male, then it makes a big difference. If your partner could go along and explain how your symptoms are affecting your life, work, relationship, etc, it will all help. The information from NHS Leeds Teaching Hospital in particular can't be disputed as this is on their official website. I doubt all hospitals have such information available online but it's worth looking to see if yours has.

After reading this over and over I think I’m finally starting to understand.

I wish I had done this sooner, I’m over whelmed.

Thank you so much for your help!

SeasideSusieAdministrator in reply to CurteisS

You're welcome.

Keep asking questions about anything you don't understand.

What is (SS)?

SeasideSusieAdministrator in reply to Lora7again

Looking at the print out the (SS) might be the initials of the doctor ordering the tests. My surgery puts the surname of the doctor in brackets after the test name like that.

perhaps youhave a photo you coukd upload to 1st post?

CurteisS in reply to Wetsuiter

Thanks, I’ve uploaded the photo now

How are you feeling at the moment and when were these tests done?

CurteisS in reply to Nanaedake

I thought I may need an increase of my dosage as I was feeling tired all the time and finding it impossible to lose weight so I went for the test in nov19 and she said that it was okay and to say on 50mg. It was confusing cause I’m still so tired all the time

Check vit D, Ferritin, folate and B12 which are all commonly low in people with hypothyroidism. Personally, I would increase levothyroxine to 75mcg and retest in 6 to 8 weeks as your TSH is quite high for someone on levothyroxine and your FT4 is on the low side. However, your fatigue may be lack of iron or other vitamins.

CurteisS in reply to Nanaedake

Yes i have low serum folate so they advised to take folic acid which I admit I have forgotten to take, so I will start taking that again.

Would I need to ask the doctor to increase this for me, is it likely they would if I asked?

Nanaedake in reply to CurteisS

If folate is low you need to check B12 level as supplementing with folate can mask a B12 deficiency. If you have a B12 deficiency it can cause neurological problems. I would get results of B12, folate, ferritin and vit D and post them here for suggestions. If not yet tested then ask doc to do them. Vitamin D most essential to test! In the meantime, return to GP and insist you do not feel well and this needs to be looked into and addressed. Are you taking other medicines that could reduce vitamin absorption?

CurteisS in reply to Nanaedake

Having a look at the blood test results they tested for serum ferritin- 77.1 ug/L , serum B12 - 155 ng/L , serum folate 2.15 ug/L, serum urea 3.8 mmo/L. This was dec18 so haven’t had that for a while.

No signs of vitamin D

And no the only medication I’m taking is Levo 50mcg

SlowDragonAdministrator in reply to CurteisS

B12 looks EXTREMELY low

Folate and B12 work together

If both are low GP should test for Pernicious Anaemia before starting on either B12 injections or B12 sublingual daily supplement

There is a high (approx 40%) prevalence of B12 deficiency in hypothyroid patients. Traditional symptoms are not a good guide to determining presence of B12 deficiency. Screening for vitamin B12 levels should be undertaken in all hypothyroid patients, irrespective of their thyroid antibody status. Replacement of B12 leads to improvement in symptoms,

Folate supplements can help lower homocysteine

Levothyroxine can decrease serum homocysteine level partly; still its combination with folic acid empowers the effect. Combination therapy declines serum homocysteine level more successfully.

You thyroid levels show you are extremely under medicated

Low Vitamin Levels are invariably the result

The aim of Levothyroxine is to increase the dose slowly in 25mcg steps upwards until TSH is under 2 (many need TSH significantly under one) and most important is that FT4 is in top third of range and FT3 at least half way through range

NHS guidelines on Levothyroxine including that most patients eventually need somewhere between 100mcg and 200mcg Levothyroxine.

Also what foods to avoid (eg recommended to avoid calcium rich foods at least four hours from taking Levo)

All four vitamins need to be regularly tested and frequently need supplementing to maintain optimal levels

See different GP and push for 25mcg dose increase in levothyroxine

Plus further testing of B12 and folate plus testing for PA plus vitamin D test is ESSENTIAL

And thyroid antibodies if not been tested yet

NICE guidelines

The initial recommended dose is:

For most people: 50–100 micrograms once daily, preferably taken at least 30 minutes before breakfast, caffeine-containing liquids (such as coffee or tea), or other drugs.

This should be adjusted in increments of 25–50 micrograms every 3–4 weeks according to response. The usual maintenance dose is 100–200 micrograms once daily.

SeasideSusieAdministrator in reply to CurteisS

serum B12 - 155 ng/L , serum folate 2.15 ug/L

This was dec18 so haven’t had that for a while.


Nothing was done!?!

According to an extract from the book, "Could it be B12?" by Sally M. Pacholok:

"We believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".

"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."

ng/L is the same as pg/ml. Serum B12 tests usually have a bottom of range level around 140-180. You should have been tested for B12 deficiency and Pernicious Anaemia at the time.

Folate sometimes has a range with a lower and upper level, and sometimes has just one figure which you must exceed, eg >3.89. I believe that your folate level of 2.15 was folate deficiency, which would go with your low B12 (B12 and folate work together) and that also should have been addressed at the time.

Please ask your GP to repeat these tests due to the fact that your levels were dire back in December 2018, if not so low as for them both to be in the deficiency category and should have been addressed at the time.

Many people with a B12 level in the 300s have been found to need B12 injections, so with a level of 155 you absolutely should have been tested back them.

Check for signs of B12 deficiency here:

If you have any then list them to discuss with your GP. Doctors are supposed to take symptoms into account rather than numbers where B12 is concerned.

Ferritin is recommended to be half way through it's range so what is the range for that test?

Have you ever had thyroid antibodies tested? Do you know if you have Hashimoto's? This is a cause of low nutrient levels/deficiencies so I wouldn't be surprised if you have Hashi's. If thyroid antibodies haven't been tested, ask for these too. GP should be able to get Thyroid Peroxidase (TPO) antibodies tested but may not be able to get Thyroglobulin (Tg) antibodies tested, an endocrinologist may have to do that. Sometimes TPO antibodies come back negative and Tg antibodies positive, so if TPO test is negative it's important to do Tg antibody test.

I was advised to take folic acid but that’s it’s.

And no I haven’t had thyroid antibodies or below tested.

I will have to get this written down and explained to my doctor, there are few things on that list that make sense for b12 deficiency

Definitely need vit D testing. B12 sounds low but I can't tell without the lab range. Do you have it? Healthunlocked Pernicious Anaemia forum are the best to answer B12 questions. If you have a good diet but B12 and folate are low and you're not taking other meds to affect absorption then you need to exclude pernicious anaemia or other gut dysfunction like coeliac disease. Both can cause fatigue. Ferritin looks alright but again, we need the lab range.

CurteisS in reply to Nanaedake

It seems I may have a lot to discuss with my doctor

Ferritin 77.1. 11.00-307.00

B12 155. 145-914

Folate 2.15. 3-20

Urea 3.8. 2.50-7.80

Nanaedake in reply to CurteisS

B12 looks awfully low. I would defo post on the pernicious anaemia forum for advice or contact the society. Check ferritin level with GP. Perhaps they should do a full iron panel. That includes TiBC.

I would think that GP will want to rule out pernicious anaemia with blood tests before you supplement with folate.

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