UCdad1,
Welcome to the forum.
Sorry aout your son's diagnosis.
The warning on the label also serves to tell those who may be sensitive or intolerant of the mesalamines, which some of us are and therefore get worse symptoms. And it's good that the warning is there, because not many docs share the possibility of the intolerance reaction with you when they prescribe the mesalamines.
As far as finding a route around Big Pharma, you'll have to find a doc who is inclined that way - probably holistic, or integrative.
I can tell you that regular meds failed me, and when my GI gave me a choice of remicade or colon surgery - I balked at both and had to find my own way.
And for me, that turned out to be a combination of diet modification, certain supplements like L-Glutamine amino acid, slippery elm powder, lots of probiotics, and LDN, low dose naltrexone.
There are things IMO that you can control, which will have a direct impact on your disease, the symptoms you experience and their severity.
I was able to control my UC into remission through various supplements, probiotics, diet modification, and LDN , low dose naltrexone.
For more info on the protocol which has put me into remission, please go to this link: https://www.healingwell.com/community/default.aspx?f=38&m=1666318 , and look at the 11th post.
I hope you feel better and let us know how we can help you.