probably the Doc. is testing you with " Dexamethasone suppression test".
don't worry it's very safe, you figure they give Dexamethasone to treat allergic shocks.
it could give you a bit of stomach symptoms and mood change during the day like hype, euphoria. it wouldn't be indicated in case you had ulceration in the stomach but not so dangerous in any case.
I figure you would already know by now if you had peptic ulcer which could explain anemia too but you'd be really messed up like fainting and vomiting. dark stool from blood in stool too. did they test you for Helicobacter pylori?
the Doc. is maybe assessing your cortisol-adrenal production, don't know why I'm not expert.
is there anything else out of range in blood count? Wbc? liver function?
My mother has had gastritis for 25 years. Today she is 95% improved after a year of digestive enzyme supplements containing proteases (enzymes that digest protein). The article from EnzymeStuff called "Digestive Disorders and Enzymes" explains in more detail. "Proteases help reduce inflammation, clean out debris and infection, and stimulate healing."
I've had the dexamethasone suppression test done with no problems. I have autoimmune pernicious anaemia (positive parietal cell antibodies and positive intrinsic factor antibodies) and this is a listed cause of atrophic gastritis. I can't feel my gastritis thankfully.
"Atrophic gastritis has two causes: 1) an autoimmune process targeting parietal cells or intrinsic factor and 2) environmental causes such as persistent infection with Helicobacter pylori bacteria or dietary factors.