The metyrapone test is used to assess the HPA axis. Metyrapone is given, which blocks the 11-hydroxylase step of steroid synthesis. If the HPA axis is intact, this results in a rise in 11-deoxycortisol to at least 200 nmol/L .

A subnormal rise in 11-deoxycortisol can be due to pituitary , hypothalamic or adrenal dysfunction.

Note that the cortisol result following metyrapone is not valid due to crossreactivity of steroid precursors and their metabolites in the cortisol assay.

Contact the Endocrinology nurses at ACH, ext 26854 for the protocol and patient arrangements.