I looked up some more information regarding a dexamethasone suppression test and hope this might give you some answers.
It is important to point out that the normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens.
Cortisol levels should decrease after you receive dexamethasone.
There is a low dose test and a high dose test. The low dose test looks to see if your body is producing too much cortisol. The high dose test helps determine whether the problem is in the pituitary gland.
Standard low dose overnight method: you are given 1 mg of dexamethasone at 11 pm and blood is drawn at 8 am. Urine is collected over 3 days. On day 2, you take 0.5 mg of dexamethasone by mouth every 6 hours for 48 hours.
Normal results are less than 1.8 mcg/dl overnight and less than 10mcg/dl urinary free cortisol on day 3.
Standard high dose overnight method: your blood is drawn in the morning. You receive 8 mg of dexamethasone at 11 pm and your blood is drawn at 8 am the next day. Urine is collected over 3 days. On day 2, you receive 2 mg of dexamethasone by mouth every 6 hours for 48 hours.
Normal results are greater than 50% reduction in blood cortisol overnight and greater than 90% reduction in urinary free cortisol.
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Hi Sara,
I looked up some more information regarding a dexamethasone suppression test and hope this might give you some answers.
It is important to point out that the normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens.
Cortisol levels should decrease after you receive dexamethasone.
There is a low dose test and a high dose test. The low dose test looks to see if your body is producing too much cortisol. The high dose test helps determine whether the problem is in the pituitary gland.
Standard low dose overnight method: you are given 1 mg of dexamethasone at 11 pm and blood is drawn at 8 am. Urine is collected over 3 days. On day 2, you take 0.5 mg of dexamethasone by mouth every 6 hours for 48 hours.
Normal results are less than 1.8 mcg/dl overnight and less than 10mcg/dl urinary free cortisol on day 3.
Standard high dose overnight method: your blood is drawn in the morning. You receive 8 mg of dexamethasone at 11 pm and your blood is drawn at 8 am the next day. Urine is collected over 3 days. On day 2, you receive 2 mg of dexamethasone by mouth every 6 hours for 48 hours.
Normal results are greater than 50% reduction in blood cortisol overnight and greater than 90% reduction in urinary free cortisol.
I hope this is helpful,
Maryann
June 17, 2013 - 5:09pmThis Comment
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