Cushing questions my Codyboy just diagnosed

[Codyboy]

Hello to you all, Codyboy and I are new to your forum. I've never joined a forum before and I hope I am doing this right. I have a few questions on this cushing's disease that my 12yr old Shilo shepherd was diagnosed with last week. My vet wants to start him on 120 mg vetporyl 1x a day to start the 44-88 pound doasage. CODYS symptoms started with the constant panting, excessive drinking and urinating, hind weakness and wasting and now bowel control, I had him checked with the orthopedic and was told he had a lot of arthritis thruout his lumbar spine and hind knees so they ruled out degenerative myopathy , I still want to get the blood test to def rule this out. That being said with Cody's symptoms and being dionosed with cushing's , when I start him on this medication will it relieve any of these symptoms and how long does it take. I would like your advice with what your fur baby has gone thru and if things got better after medication. Thank you all .
Cortisol-pre. 4.9. Reference 1.0-6.0 ug/dl
Cortisol-4hr 4.6. Reference
Cortisol-8hr. 2.6