Crohn’s disease and ulcerative colitis vary greatly in their severity. Some people have minimal symptoms every few years. Others have severe symptoms almost nonstop. 
Our general approach is to start with milder medications to treat milder diseases and reserve stronger medications, with their associated risks, for more severe disease. 
Sometimes the image of a pyramid is used to explain how IBD medications are prescribed. 
At the bottom are medications that are used more widely and milder in both risk and benefit. 
At the top are medications that are more potent but also have more significant side effects. 
In the step-up approach, patients work their way up the pyramid. Many IBD providers and researchers believe in starting patients in the middle of the pyramid and not waiting for the disease to get worse before prescribing more potent medications. They take this approach to reduce the chances of patients developing complications from Crohn’s disease and ulcerative colitis.
Here at the Brigham and Women’s Crohn’s and Colitis Center, we believe that one algorithm does not fit all. We look at each patient as an individual.  We will asses the severity and aggressiveness of your disease, along with a host of other factors, to determine if you would be best served by the top-down or bottom-up approach.
Regardless of the approach, you need to continue taking your medications, even after you start feeling better and when you have few, if any, symptoms. 
If people with IBD stops taking their medications, their disease is very likely to flare.