Once you start getting on Hydrocortisone it is kind of too late to get tested for it. However, as the doctor who put me on it told me, doctors used to go by symptoms. I most definitely have the symptoms. Btw he also said that blood tests are often misleading. For ex. he said that when he first began practice, decades ago, that "average" really was normal. What they call "average" i.e. "normal" today has changed, has dipped, he said, because we have a less healthy population due to things like toxins and depleted soils. Low average, for ex. can really mean a deficiency. We should go for optimal, not average. MDs have been known to misdiagnose, misinform and be dismissive of serious Qs and problems. They have been known to be basically shills for Big Pharma. And this I have unfortunately observed too often in my own personal experience with them. I avoid them amap. I know alternative health practitioners can be very inaccurate and misguided too, but I don't ever go to any of them.