Been there, done that. Here is my post from several years ago. I have also linked two educational threads for your review. Keep in mind they are several years old and treatment recommendations may have changed and protocols may have evolved since I last reviewed this information. I still miss my old guy…
Cushings is not a great diagnosis but there is a fairly long period where it develops, which gives you plenty of time to love up your dog. My dog’s first symptoms were a pot belly, scruffy hair coat, and excessive drinking and peeing. Good luck. Keep us posted.
I have been down that road with my Boxer. He lived with Cushings for nearly 18 months and I would do it all over again. We had ACTH stim tests done regularly to make certain the meds were controlling it. We chose to go with Lysodren which is powerful but worked for him. We always knew when he was getting ready for an ACTH stim and an increase in his dosage because his peeing and drinking would ramp up. We got to the point where we were sweet talking him when he would trickle-pee in the house - we didn’t want him to feel naughty about something that was clearly out of his control. Best thing we did was keep him as active as he would tolerate. Cushings can cause muscles in the back end to waste away so maintaining fitness is crucial - within reason of course. He got pretty creaky at the end and we even did acupuncture and chiropractic work on him to keep him comfy. There is a lot I would give right now to be wiping up his pee from the kitchen floor one more time. I relish every day I have with my dogs because our time together is simply too short.
Two threads on Cushings you might find helpful.
https://www.chronofhorse.com/forum/forum/off-topic/the-menagerie/284240-cushings-in-dogs
https://www.chronofhorse.com/forum/forum/off-topic/the-menagerie/190058-cush-pups?352884-Cush-pups=&highlight=Cushings