I have used Androgel since I was 37 back in 1998. First packets, now the pump bottle. It was prescribed by my Endocrinologist for an unrelated pituitary condition, but my GI tests my T levels and recommends keeping up with the Androgel because it fosters good red blood cell production in the bone marrow. I bleed daily, and anemia has been a serious problem this year. Anyway, nobody mentioned, and I did not come across, any concern about Androgel making UC worse.
That said, I am hesitant to encourage any self-mediction, or use of anabolic steroids, without medical supervision.