Trying to learn again

[Dryski]

Can anyone tell me why they test tsh when your on medication if it really serves no purpose. Isn't the free t3 and free t4 the main goal.

[jimh111]

IF the pituitary is working normally TSH is a good indicator of the individual’s hormone status, it will reflect the combined effects of fT3 and fT4. Its usefulness can vary. For example, in newborns a TSH assay can prevent cretinism. For patients on levothyroxine monotherapy TSH usually has to be lower than average and fT4 in the upper half of its reference interval. (I don’t advocate levothyroxine monotherapy because a higher fT4 carriers cardiac and cancer risks).

Patients who need T3 to recover wellness often need a lower, or zero, TSH either because they have some form of resistance to thyroid hormone,or more likely, their pituitary is not fully functioning and so secretes insufficient TSH.

It’s not a black and white situation.

[Dryski in reply to jimh111]

Thanks. I'm on levo only and could use an increase but my new doctor won't budge because of the whole deal about osteoporosis and atrial fibrillation becoming a possibility. They won't bother to test t3. I was not aware of this road block till now. I've jumped all the hoops 12.5 at a time through the years but I quess 125 is my final dose for now. Thanks for letting me vent.

[waveylines in reply to Dryski]

Honestly the only way to be optimally treated is to become very knowledgeable on hypothyroidism. Most GPs know shockingly little. They are taught that if TSH is in range all is fine. That's the barrier you are hitting. If you dint feel well you will have to see an Endo but most of them specialise in diabetes not hypothyroidism so highly likely to know little as well. I don't know your blood test results. Can you post them? Was it just the TSH they did. This seems to be the new edict that the NHS has put in place to save money.

[DippyDame in reply to Dryski]

Given that T3 is the active thyroid hormone( that is, once it reaches the nuclei of the cells and the T3 receptors) it beggars belief that FT3 testing is rarely considered necessary

This explains the testing history

thyroiduk.org/testing/histo...

Depending on your current labs 125mcg may not need to be your final dose! I took 200mcg before the dose proved too much!

We need to avoid over range FT4 which carries increased risk to the heart and increases cancer risk...how high is your FT4? Excess FT4 can be converted to reverseT3 which is metabolised and eventually excreted....it does no harm but is an indicator that something else is wrong. Poor conversion being one.

Our T4 to T3 conversion rate is an important factor clearly if this is low FT4 will be high and FT3 low.

Do you know how well you convert? Probably not if FT3 isn't tested!

If conversion is impaired ( and we need to optimise vit D, vit B12, folate and ferritin to support conversion before deciding that) we need to add T3 to maintain an adequate level.

For good health almost every cell in the body must be flooded with T3 by way of a constant and adequate supply....if either is neglected our health suffers.

What symptoms do you have? Medics are supposed to consider those along with labs.

Some people can achieve an adequate level of FT3 by raising the FT4 result close to the top of the range... beyond that T3 replacement is required.

Trying to adjust TSH just doesn't provide a reliable as the following papers show

bmcendocrdisord.biomedcentr...

Time for a reassessment of the treatment of hypothyroidism

John E. M. Midgley, Anthony D. Toft, Rolf Larisch, Johannes W. Dietrich & Rudolf Hoermann

*********

thyroidpatients.ca/2021/07/...

Full thyroid testing is esential...but sadly it is not the NHS way! My surgery routinely tested FT3 until 2000 and problems then arose

Have you requested an appointment with an endo who should be more clued up!

Many of us have to test privately

thyroiduk.org/testing/priva...

It's your body and your health don't let a poorly informed medic keep you unwell

Sorry it's a bit of a rant but hopefully something resonates.

Good luck!

[SlowDragon Administrator]

If not done so yet you need to test vitamin D, folate, ferritin and B12 too

Low vitamin levels will result of inadequate dose levothyroxine,

Low vitamin levels result in poor conversion of Ft4 (levothyroxine) to Ft3 (active hormone)

[serenfach]

The TSH test was developed to find out if the thyroid was working in those not taking any thyroid medication - an initial test.

It still gives some indication as to how satisfied the body is when you are taking thyroid medication, and can be useful to point to pituitary problems. The trouble is most medical people dont understand this and dose by TSH alone, completely wrong.