Re: Molly, 10 yr, shih tzu - lhasa aspo, cushing diagnosis
If you are trying to control the intermediates, UTK recommends 3mg 2x/day for a dog Molly's size. That is what Squirt started at then ended up taking 12mg 2x/day (per her IMS) before we stopped all meds. When I started these back, it was at 3mg 2x/day planning to build back up but we never did. She did fine with the melatonin after the initial adjustment period. Since UTK has done the research on this, I never thought to question the 3mg dose - I simply gave it believing it would help with her hormones, and it did. If it were me, I think I would contact UTK and see what they think - if they will talk with you. Since Dr. Oliver passed, they aren't as willing to interact with the "public" as he was but you never know. But if other pups have had a hard time adjusting surely they know this and can direct you a bit. Hopefully. 
Since the Mexican seems to be out, don't forget about the lobster!
You could serve them on tostitos for a blended cuisine.
"May you know that absence is full of tender presence and that nothing is ever lost or forgotten." John O'Donahue, "Eternal Echoes"
Death is not a changing of worlds as most imagine, as much as the walls of this world infinitely expanding.