Hi there,
I have had a j-pouch for about a year now, after being diagnosed with FAP ~15 years ago. I appreciate the post from closeau, and what others have shared. I would like to share part of my journey and some additional info. TL;DR at bottom 
The last year has been rough, including many painful episodes of intense naseau and pouchitis that i feared were, and appeared to be, becoming chronic. Either that or SIBO, but either way it was extremely painful and depressing and was breaking me down, both physically and emotionally. At wits' end, I even considered having the pouch removed, among other things...
Doctors kept wanting to throw drugs at me, and after around 6 months of taking all different types of (some heavy) meds that seemed to just be masking symptoms and causing more problems, i had had enough.
I stopped all prescriptions and switched to a strictly cannabis regimen. I have self-medicated with cannabis for 20+ years, but now focus on more CBD (cannabidiol) based medicine. I have been nearly symptom free since; unfortunately it does not cure being a glutton...
What it does cure: CBD is primarily non-psychoactive and displays many medicinal properties (anti-inflammatory, anti-carcinogenic, anti-ischemic, anti-nauseau, etc etc), without the negative side effects typically associated with THC dominant cannabis/medicine, as mentioned by some in this thread (memory loss, mood swings, etc).
While THC may not be for everyone (studies have shown that high levels of THC may excite the same neuronal pathways associated with bipolar disorder, important to consider if you are having strong/frequent mood swings), CBD based medications have proven safe and effective for patients of all ages and diverse medical needs.
Here are some links to get started:
https://en.wikipedia.org/wiki/Cannabidiol (general info and links)
http://www.projectcbd.org/colitis-crohns-disease (links to medical journal articles)
TL;DR - Pouchitis sucks, strong cannabis/THC isn't for everyone. CBD (cannabidiol) might be exactly what you're looking for; its working for me (and many others)!
Feel free to message or reply here with any questions or requests for links etc!
Thanks, hope this helps,
Lance