@ttobler Yes. I had a bitch who didn't need a vet at all until she was almost 6 years old. Then the kibble we used was discontinued. We found what we thought was similar but one girl started being very sick, not eating, but chewing grass and throwing up etc. We jumped through all the hoops until finally an endoscopy revealed Irritable Bowel Syndrone. The lining of her stomach was red, raw and bleeding. No wonder she ate so much grass to try to get rid of the pain and irritation in her tum !
She was put on Budesonide. One a day. And given a grain-free diet. I tried feeding her that and leaving the others on their normal kibble but it was chaos. We had 5 Basenjis at the time. So all the pack went on to the grain-free and I have stuck with it ever since !
After a while she seemed to be really on the road to recovery and the vets left it to me to control the dosage of Budesonide. I cut her to every other day and then to three times a week. If I caught her eating grass, she went back on one a day for a week or so.
This way we kept her going, and enjoying life, for another 7 years.
I am sure you can find the USA equivalent of Budesonide. Good luck !