Thyroid gland and thyroxine

Why do some young people with conditions affecting their hypothalamus and pituitary gland need to take thyroxine?

The pituitary gland produces a hormone called thyroid stimulating hormone, TSH for short, and as the name suggests this hormone stimulates your thyroid to make a hormone called thyroxine. This means that if the pituitary gland cannot produce TSH your thyroid gland will not be able to make thyroxine. Mostly your thyroid gland is healthy it is just the messages from the hormones from the pituitary gland that are wrong. One possible exception to this is in young people who have had treatment for leukaemia or a tumour with radiation treatment the thyroid gland may have been damaged as well as the hypothalamus and the pituitary gland.

How will I know if I am not producing enough thyroxine?

If your thyroid is not working properly because you are not producing enough TSH people can experience – growing less well, putting on weight despite eating the same, feeling cold when everybody else is warm, getting constipated, generally feeling a bit tired. The doctors may pick it up first by doing routine blood tests. They may find that your thyroxine levels are low.

If I have a thyroid problem how will it be treated?

It is easy to give you the thyroxine back that your thyroid gland is not making, it comes as a small tablet that has to be taken every day. Try and find ways to make it easy for you to remember. Your doctor will check the dose is right for you by checking to see that your thyroxine levels are in the normal range and also how you feel (so tell them).

Questions you could ask your doctor or nurse

  • Do you think my thyroid is damaged as well as my hypothalamus and pituitary gland?
  • When is my next thyroid function test due?
  • If my thyroid function is normal why do I feel tired?