I've been using slippery elm powder (organic) for several years now and it's great. IMO it is much better than mesalamines.
It helps eliminate acid reflux and GERD.
It coates the whole intestinal tract.
When I was flaring, I used to take it after every meal.
I would make a "cocktail" of it, in 1-2 oz of room temp filtered water, I would add 1 heaping teaspoon of it, + probiotics, mix it well and drink it down.
Since being in remission, I still take it after dinner.
There are different qualities of it, some poor and some great.
The pills are useless. And I would only recommend the organic slippery elm powder ( it's about $20 per pound, but that pound probably lasts a good 6-9 months depending on usage). Well worth it and pretty cheap for something that works great.
As has already been mentioned, you do need to take it apart from any meds (due to absorption problems) by 2-3 hours.
BTW, you've probably heard of the fiber called psyllium husk or psyllium seed husk powder - well the same is true of it, any meds need to be taken 2-3 hours apart from it too.
Anyway, it's certainly cheap enough that you could try it and see how you do on it, no?