I've lost a total of 25-30lbs. over the past 2-3 years- most of it during one horrible flare, in 2007. Now, I find I just cannot put weight on- I don't cinsider myself to be in a flare right now, but I do have daily symptoms that can wreak havoc with my life. And I do take a lot of meds. I think the inability to gain weight is caused by a few factors- I don't eat as much as I used to, pre-UC, because of the obvious reason. Also, when your body is in a state of inflammation, it burns more calories than a healthy body, fighting the inflammation. Unless I start a regime of weight lifting, I can't see how to add muslce pounds- and I get tired too easily to actually work out! I like to swim laps, but that does nothing to put on weight. Since you are flaring curently, you can expect to see weight loss. I can't imagine you're eating all that much!