Crohn's Disease (cont.)

Immuno-modulators are medications that affect the body's immune system. The immune system is composed of immune cells and the proteins that they produce. These cells and proteins serve to protect the body against harmful bacteria, viruses, fungi, and other foreign invaders. Activation of the immune system causes inflammation within the tissues where the activation occurs. (Inflammation is, in fact, an important mechanism used by the immune system to defend the body.) Normally, the immune system is activated only when the body is exposed to foreign invaders. In patients with Crohn's disease and ulcerative colitis, however, the immune system is abnormally and chronically activated in the absence of any known invader.

Immuno-modulators decrease tissue inflammation by reducing the population of immune cells and/or by interfering with their production of proteins. Decreasing the activity of the immune system with immuno-modulators increases the risk of infections; however, the benefits of controlling moderate to severe Crohn's disease usually outweigh the risks of infection due to weakened immunity. Examples of immuno-modulators are:

• 6-mercaptopurine (6-MP),
• azathioprine (Imuran),
• methotrexate (Rheumatrex, Trexall),
• infliximab (Remicade),
• adalimumab (Humira),
• certolizumab (Cimzia), and
• natalizumab (Tysabri).

Source: MedicineNet.com
http://www.medicinenet.com/crohns_disease/article.htm