6-mp does not just treat symptoms. It treats disease activity by lowering the body's immune response. The current thinking is that crohn's disease is an auto-immune disease. That means that the body's immune system begins to view the body's own tissues -- in this case intestinal tissue -- as a foreign invader. It mounts an immune response in order to "fight" this "invader" and that's how the intestinal tissue is damaged. Eventually, if this immune response is not controlled, as the the body tries to heal the ulcerations and inflammation scar tissue forms. Each flare produces more inflammation and ulceration and thus more scar tissue. Immuno suppressents like 6-MP and Imuran shut down the body's immune response so it stops attacking the intestine.
It sounds like your docs might be concerned that you have a primarily stricturing form of crohn's. There is some concern (althout the most recent studies seem to refute the hypothesis) that Remicade works so well at healing that, in stricturing crohn's, it can excellerate the formation of scar tissue. If you already have a narrowing from stricture, the thinking is that it might actually exacerbate symptoms (make the stricture worse). If however, your symptoms are primarily the result of inflammation or you are suffering from fistulas, then Remicade is a treatment of choice because it has been shown to be highly effective in both reducing inflammation and healing fistulas.
There are three major forms of crohn's disease -- in some people the disease is primarily the stricturing type, in others the most pressing issue is inflammation, and still others have primarily problems with fistulas. To some extent any crohn's patient can experience all of these manifestations (I have) but I have primarily stricturing crohn's so my most pressing concern is scar tissue formation. Since my last surgery, 2005, I am being maintained on 3000 mgs of pentasa and 100 mg of imuran and feel I'm closest to clinical remission as I have ever been in the 30 years I've been dealing with this disease.
I know it is hard to be patient, but give your medications time to work. Typically it will take from six weeks to six months for 6-MP to become fully effective. While there is a body of thinking that suggests a top down approach to treating crohn's -- using the most powerful drugs at the beginning in order to knock down the disease before it has had time to do lots of damage -- this is still a very controversial therapeutic approach, especially in view of the fact that the immuno-modulators like remicade become less effective with continued use and have a high potential for very nasty complications.
30+ years living with Crohn's.