The nonstenotic, nonfistulizing (or inflammatory) pattern of Crohn's disease appears to be unstable in time and may evolve toward either the stenotic or the fistulizing pattern. We aimed to assess the course of the inflammatory disease and its relation to certain clinical characteristics. After a mean follow-up of 93 months, we evaluated 73 patients with an inflammatory pattern. The behavior trend and its relation to disease location, initial treatment, and need for corticosteroids, immunosuppressors, and surgical resection were analyzed. In 64% of the patients the inflammatory pattern did not change, while in 14 and 22% it evolved toward a stenotic and a fistulizing pattern, respectively. This change was mainly determined by the appearance of perianal disease (75%). The mean time to behavior evolution was 67 months. Most patients required corticosteroids (92%). Need for immunosuppressors (48%) and surgical resection (30%) was significantly greater (P < 0.05) among patients with a change in pattern than in those with persistent inflammatory disease. The inflammatory pattern of CD remains stable in about half of patients. The course of this pattern is not indolent, however, since the needs for immunosuppression and surgical resection during follow-up are considerable.