Welcome to the forum.
IMO, alot of the fatigue can sometimes come from the mesalamines.
And also malnourishment (due to malabsorption of foods, nutrients, etc...).
A few questions, you can blood work came back normal?
They don't always check for vitamin d3 and b12, did they check these?
Keep in mind that low levels of vitamin d3 are associated with UC, fatigue, depression, among many other diseases. Many people have levels of 29-30, which docs consider normal.
But in fact research has shown that adequate levels should be in the 40-50 range, and I have even read that for those with auto-immune diseases, that number should be closer to 50-60. I keep my levels in the mid-60's.
Are you taking any supplements?
There are other things you can do for your UC symptoms which might help more than just the meds, for your UC health which might mean less fatigue and perhaps even the ability (eventually) to reduce some meds.
If you are interested, 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.
Rx meds didn't help me. But 4.5 mg LDN +Paleo diet +supplements=REMISSION.Protein shakes w/almond milk,Maca powder,L-Glutamine,D-Ribose,chia seeds.VSL#3,K2,VIt. D3,slippery elm bark powder.For more info,my protocol is the 11th post at this link: https://www.healingwell.com/community/default.aspx?f=38&m=1666318
If you have any questions, you can find my email address at my profile.