sadie-mae

Hi Grace,

If you are going into hospital for your ITT, you will be in good hands. I am very happy to hear they are checking your growth hormone as well as your cortisol during the test-might as well maximize the info!

They are running this test because your doctor is concerned that you have pituitary failure causing your symptoms. The pituitary gland (at the base of your brain) makes hormones that, in turn, stimulate other hormones in your body. For this test in particular, they are evaluating your pituitary's ability to make enough ACTH ( which is what stimulates release of cortisol from your adrenal glands) and growth hormone (which is made directly in your pituitary).

The benefit of this test is that it is very sensitive and can catch even mild decreases in function. It is considered the "gold standard" for testing for both Addison's disease and growth hormone deficiency.

That said, the drawback to this test is it can be somewhat uncomfortable. They will give you insulin to cause your blood sugar to drop to about 40 (normal is above 70). This can leave you feeling woozy, faint, sweaty, shaky, with low blood pressure or even nauseous. Everyone is different and they will monitor you carefully (blood pressure, heart rate, breathing rate, blood sugar) to be certain you are okay during the test. If you run into difficulty, they will give you IV glucose (sugar) to get your blood glucose levels back up again. Most people find it unpleasant but do just fine with it. It is contraindicated if you have a history of heart disease and you should talk to your doctor if you are concerned about that risk.

It will give them excellent information about your pituitary function and that will hopefully point the way to answers about what is making you sick. I wish you good luck and please let us know how you did (I've never had this test-so I can't personally say what it is like...).

Sadie