New test results : Hi all Pease could I have a... - Thyroid UK

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New test results


Hi all

Pease could I have a little help.

12 th July.


Serum TSH level < 0.01 mIU/L [0.35 - 4.94]

Serum free T4 level 20.90 pmol/L [9.01 - 19.05]

14th May

Serum TSH level < 0.01 mIU/L [0.35 - 4.94]

Serum free T4 level 17.70 pmol/L [9.01 - 19.05]

(Missing 3 days of medication before blood test)

16 March

Serum TSH level < 0.01 miu/L [0.35 - 4.94]

Serum free T4 level 20.8 pmol/L [9.01 - 19.05]

Serum free triiodothyronine level 3.9 pmol/L [2.63 - 5.7]

Any help will be nice.


5 Replies


Why did you miss 3 days meds before your May test? That gave you a false low FT4.

When did you take your last dose of thyroid meds before your July test?

What dose of thyroid meds are you taking?

I was going to go for a blood test on the Friday. And someone turned up late for work. So missed the walk in blood test. For got my medication on the Saturday and be time I got home it was to late. Sunday it just clear went out of my head. Monday I’d took them after the blood test at 9 in May.

The blood test, is taken in July was at 9.30am. And medication last taken at on the Sunday at 7.30 in the morning.


Levothyroxine sodium 175 microgram tablet

in reply to Haze1975


OK, so your July results suggest that it would be a good idea to get FT3 tested at the same time as FT4.

Your FT4 is just slightly over range but if those were my results I would want to see how well I was converting.

Haze, just going by your March results, your FT3 is too low in comparison to your FT4. At that point he should have tried to determine why. Often something is interfering with conversion from the inactive T4 to the active T3. Some of the reasons are excess estrogen, low iron or too high or too low cortisol. Estrogen is in many foods and also the pesticides used on foods. It's too bad that real investigation is not done so treatment can be modified. You probably should be adding T3 or using an NDT that contains T3 under these circumstances.


Would suggest you get FT3 tested and at same time vitamin D, folate, ferritin and B12 tested too

Likely to need to do this privately

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.

All thyroid tests should be done as early as possible in morning and fasting and don't take Levo in the 24 hours prior to test, delay and take straight after. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)

You look likely to be poor converter. This can be due to low vitamins. Getting these tested and FT3, FT4 and TSH altogether is first step

If FT3 is low then you may need addition of small dose of T3

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,

"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)."

Professor Toft recent article saying, T3 may be necessary for many, especially if had thyroidectomy or RAI

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