Jackson was tested for this (ACTH test) as he had almost all the symptoms. Test came back negative.
He had diarrhea for over a month in Dec into January. So frustrating and scary. Also some vomiting but not much. We did every test under the sun.... I was shocked when the Addisons came back negative.
Otherwise, I do not know a ton about it, but I am sorry you are going through this.
If you need any other tips and tricks about what I did and what stopped the diarrhea for Jax, let me know.