We studied the use of unconventional therapies of a well-defined population of 105 patients with inflammatory bowel disease (IBD; 72 with Crohn's disease and 33 with ulcerative colitis) who were attending a university out-patient clinic. The following items were used to compare those patients who used unconventional therapies with those who did not. We compared disease-related data, sociodemographic variables, patients' disease-related concerns, and their perceived level of information about IBD. Concerns were measured with the Rating Form of IBD Patient Concerns (RFIPC), inflammatory disease activity was assessed by physicians with the Crohn's disease activity index (CDAI) and the clinical activity index (CAI). Of the 97 (92.4%) patients who answered all questions, 33 (34%) reported using unconventional therapies in addition to conventional therapy. In their level of information about IBD and in their clinical and sociodemographic data, they were not different from the IBD patients who were not using alternative treatments. In their duration of disease, there was a significant difference (p < 0.0002). The longer the disease duration, the more often patients used unconventional therapies. The most important differences between users and nonusers were the following: patients who used unconventional therapies were more concerned about having surgery (p < 0.001), being treated as different (p < 0.04), and feeling out of control (p < 0.05). We conclude that there is a relationship between the use of unconventional therapies and some disease-related concerns, which should be considered in clinical practice. This may help these patients avoid using unproven and expensive alternative therapies.