Welcome to the forum.
If you're having symptoms and yet your colonscopy was clear, what exactly did your GI say all your symptoms are due to?
I've never heard of prednisone causing brain damage, though who knows?
Have you given any thought to trying LDN, low dose naltrexone - to modulate your immune system and get thing working better with fewer symptoms maybe?
Do some research on LDN - low dose naltrexone, you can search this forum as they are several threads on this. I can tell you it works!
Here's the Penn State research done by Dr. Jill Smith with LDN and Crohns Patients.
What do you think?
Dx - UC 09/2010.Tried various Mesalamine enemas/suppos/pills with Prednisone for several rounds without any help.PaleoDiet of proteins,veggies,salads, fruits, & protein shakes w/almond milk, Liquid Minerals& Vitamins,Maca powder,L-Glutamine 15g, D-Ribose 5g,L-ArgEthylEster,chia seeds,VSL#3,K2,VIt. D3 100,000 IU every 10 days.Transdermal LDN put me remission!