corbinam
Moderator
I can only speak anecdotally regarding a good friend's older rescue (perhaps 8 - 10 years old ?). She was diagnosed approx 1 year ago and is being treated with lysodren. They have had to tinker / adjust the dosage (both up and down), but the dog is doing extremely well and you would not know that it has Cushings.
I know a woman (lives near my in-laws) who has a sheltie with Cushings. You would honestly never know anything is wrong with her. She is on some sort of medicine that she takes daily, and she runs and plays with our dogs every time we go visit.
She does tire a bit faster than our dogs, but she still runs around like crazy!