Just from the top of my head so I might be being really dumb here - but I think the ’u’ symbol means micro so ug/dL is the same as mcg/dL.

Again I may be being really dumb here - my brain’s on overload, so could someone clarify for me.....I thought that it wasn’t possible to get an accurate blood ’cortisol’ level while on Dex or Pred however it is possible to test cortisol level while on hydrocortisone!!!