Newly diagnosed - Any success stories with Tristolane?

[Bamafanroz]

My name is Roz. My baby is Rex. He is a 12 year old Teddy Bear ( half Bischon and half Shiz Tsu). He is fairly asymptomatic with only slight increases in drinking water and urination but wakes us up 3-4 times a night to potty. Proteinuria +2 - ALT 196 and ALP 520. Also elevated cholesterol 442. Platelet count also high at 480. Glucose not high yet but super high “normal”. Then ran Bile Acid test and cortisol blood work. Bile acid normal and cortisol high. He weighs 16.9 lbs now.

Had all this blood work done because of pre-dental anesthesia. So.......dexamethisone suppression test was next.
Cortisol pre-Dex: 8.7
Cortisol 4 hr post Dex: 0.7
Cortisol 8 hr post Dex : 6.7

Vet says Pituitary dependent Cushings disease is his diagnosis.

I want to treat. Vet wants to treat with Vetoryl 10mg once daily to start with follow ups to determine dosing.

My question is - Are there any positive stories treating with Vetoryl? After reading some of the posts, I am now frightened.
I could use some advice here. Anything will help!

Thanks in advance for helping me through this!