If you get radiation done on Thyroid, whats the use of TSH level? Thought its not functioning?

[sarajuarez2912]

Just wanted to know why levels are still checked on Thyroid if those that took radiation pill had it burned out. Thanks

[jimh111]

TSH stimulates the thyroid to produce hormone. The thyroid hormones also feedback on the pituitary to suppress the production of TSH - a negative feedback mechanism. Thus, TSH can be used to reflect blood levels of thyroid hormone. TSH is usually an accurate marker of overall thyroid hormone status. (This is not always true, there are several ways this mechanism can go wrong. Unfortunately, endocrinologists overlook this.)

After thyroid cancer it is sometimes necessary to suppress the TSH to reduce the chance of the cancer coming back. This used to be done always but now they can grade the cancer and in many cases the TSH does not need to be suppressed.

So TSH is measured for two reasons: -

1. As a guide to your blood hormone levels. In this case, it is important to give priority to your symptoms, so don’t let your doctor go purely by the blood test.

2. To prevent a thyroid cancer coming back.

[Clutter]

Sarajuarez2912,

The pituitary gland which issues TSH doesn't know that the thyroid gland has been ablated. It will issue TSH until it detects sufficient T4 and T3 so TSH can indicate whether the patient is receiving adequate thyroid replacement.

[Angel_of_the_North]

Your pituitary doesn't know your thyroid is dead, so it still sends signals to produce more T4 and T3 if you don't have enough. Therefore, a high TSH is relevant (along with Ft4 and Ft3) as it probably means that you aren't on enough meds (or you have a TSH-producing adenoma - unlikely - if your TSH is high and Ft4 and FT3 are at the top end of their ranges), A low TSH isn't really relevant (unless FT4 and FT3 are over range) as it just means that your pituitary knows that your body is getting T4 and T3 from somewhere, so no signal needed.

[Glynisrose]

Many doctors use the TSH as a guideline, they are wrong if you have NO thyroid then go by how you feel not numbers. You can defy your doctor by following the basic rule of 'I feel OK therefore I am OK. ' and stick to it use the broken record method if you need to.

[Roma26]

I had an overactive thyroid and the doctor was going to get rid of it but after going to the specialist he said they are trying a new method. That was high doses of the meds. It did work, still have thyroid....no problems. Don't know what your problem is but would avoid getting rid of thyroid unless absolutely necessary.

Rosa

[sarajuarez2912]

Thanks Rosa. I still have my Thyroid. I just wanted to know about the readings if supposedly some have had to burn off their Thyroid with radiation pill. Oh I don't think I could go through that. I was reading up on stem cells and what a prognosis it has made. I hope it was already used on people who are greatly suffering. Thanks for comment. And glad your Doctor is working with you, to better you more.