L,
Welcome to the forum.
Many doctors don't tell their patients about the side effects and intolerance that mesalamines can create.
But IMO, yours is an intolerance problem.
There are other things you can do, which are much more natural, and work very effectively: probiotics, slippery elm powder, l-glutamine amino acid powder, diet modification.
If you are interested in any of these, 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.