Help needed interpreting test results - Thyroid UK

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Help needed interpreting test results

Glasgow_girl profile image
1 Reply


I've just had some results back from Medichecks regarding my thyroid function. I've had symptoms for years, but every time I've been tested previously, the GP just said the results were 'normal.'

Here are the results (range in brackets):


FREE THYROXINE 12.700 pmol/L (12.00 - 22.00)

FREE T3 5.92 pmol/L (3.10 - 6.80)

THYROGLOBULIN ANTIBODY 14.900 IU/mL (0.00 - 115.00)


Thank you.

1 Reply
HughH profile image

TSH is not a thyroid hormone. It is produced by the pituitary gland and travels in the blood to the thyroid gland where it signals to the thyroid gland to produce more thyroid hormones.

Your TSH is in the higher part of the normal range and if above range could indicate hypothyroidism.

Thyroxine (T4) is a thyroid hormone but is not an active hormone, it needs to be converted to T3 to become active.

Your Free T4 is at the bottom of the normal range but this needs to be interpreted in conjunction with the Free T3 value.

T3 is the active thyroid hormone which controls the metabolism and therefore the symptoms. Your Free T3 is in the top part of the normal range, which is good, so you do not have hypothyroidism.

Your low in range Free T4 in conjunction with good Free T3 shows that you are converting T4 to T3 well. With your good Free T3 the TSH would normally be low but your TSH could indicate that your body wants a higher Free T3.

As you are having what appear to be hypothyroid symptoms, one possible cause is a genetic condition commonly known as Thyroid Hormone Resistance. It causes hypothyroid symptoms and requires very high T3 levels (often above the top of the normal range) in the body to overcome the resistance.

As it is genetic if there are other family members with thyroid problems, fibromyalgia, CFS, ME, Coeliac Disease, MS, Heart Disease or depression this would further support this possibility. Even if you cannot identify any family history of this it is still possible that you have this condition.

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