Synacthen is a manufactured drug that acts like ACTH by stimulating the adrenal gland to produce more cortisol. By measuring the rise in cortisol in the blood the doctor can see if the adrenal glands are secreting normal amounts of cortisol and the pituitary gland normal amounts of ACTH. How is the sample collected for testing? A blood sample will be taken and then the synacthen injected, at which point the time is recorded and…Synacthen is a manufactured drug that acts like ACTH by stimulating the adrenal gland to produce more cortisol. By measuring the rise in cortisol in the blood the doctor can see if the adrenal glands are secreting normal amounts of cortisol and the pituitary gland normal amounts of ACTH. How is the sample collected for testing? A blood sample will be taken and then the synacthen injected, at which point the time is recorded and further sample(s) taken according to the local protocol. Alternatively a needle or small polystyrene tube (a cannula) with a valve mechanism on the end is put into a vein in your arm. The end is taped to your arm and remains in place during the test. A baseline blood sample is taken through the cannula before the test. A solution containing synacthen is then injected into the vein. After 30 minutes a second sample of blood is taken. Cortisol is measured in the blood samples. Is any test preparation needed to ensure the quality of the sample? Exogenous steroids (glucocorticoids) should be stopped at least 24 hours before the test e.g. prednisolone, and inhaled steroids should not be taken the morning of the test. Those taking oestrogen replacement of the oral contraceptive containing oestrogen should ideally stop 6 weeks prior to the test (alternative forms of contraception should be used). The test should not be performed within 6 weeks of pituitary surgery. Smoking and strenuous exercise should be avoided during the test. Please discuss with your healthcare professional prior to the test being performed. See MoreSee Less
