The most disheartening thing my Dr. told me when I got diagnosed with IC was that "we don't know" what causes IC. If you go with the bladder lining degeneration theory, take Elmiron. If you go with the nerve theory, take the antidepressant. If you go with the histamine theory, take the antihistamine. I can't remember what the fourth was. But none of these treatments was really "curing" anyone or getting to the root cause.