Found this information on one of the sites provided above. Thought I would post for anyone else looking.
Dogs with Cushing’s disease should be fed a high-protein diet. Protein can help prevent muscle wasting. High quality proteins are also good for the skin and immune system. Also, since dogs with canine Cushings disease are prone to develop hyperlipidemia (high cholesterol and triglycerides) and pancreatitis, the amount of fat in the diet has to be moderately low.
Finally, dogs with this disease are susceptible to the formation of calcium oxalate bladder stones. Therefore, avoid giving them too much calcium and vitamin C. Also make sure that they have plenty of water intake to avoid stone formation. – See more at: http://www.natural-dog-health-remedies.com/canine-cushings-disease.html#sthash.9TDdaP2J.dpuf
Also said these herbal drops may help also… http://www.nativeremedies.com/petalive/products/cushex-cushings-disease-remedy-for-dogs.html?cj=3036157#ysmtac=cj&ysmchn=affiliate&ysmcpn=cj&ysmgrp=3036157
