Chronic diarrhoea is a common condition, resulting from a number of different disorders. Bile acid diarrhoea, occurring in about a third of these patients, is often undiagnosed. We hypothesised that a positive diagnosis of BAD would reduce the need for subsequent investigations for alternative diagnoses.Methods: Patients previously recruited to a study of chronic diarrhoea who had SeHCAT testing and subsequent follow-up at our institution were identified. In a retrospective analysis, the numbers of defined investigations undertaken from the first three months after SeHCAT in the following 5 years were compared.Results: 90 patients were identified with primary bile acid diarrhoea (SeHCAT retention <15%, n=36) or idiopathic diarrhoea (SeHCAT retention >15%, n=54). Follow-up had been performed on 29 and 39 subjects respectively, with no differences in previous investigations or the last contact date. In the follow-up period, the proportions of these patients who had undergone endoscopic procedures (gastroscopy, colonoscopy, sigmoidoscopy) were the same. However, there was a higher proportion of patients in the SeHCAT-negative group who had undergone other investigations, including imaging, physiological tests and blood tests (p=0.037). Use of cross-sectional imaging was significantly higher in this group (p=0.015) with greater proportions of subjects having CT (0.44 vs. 0.10) and MRI (0.26 vs. 0.07). Ultrasound use and the number of blood tests were also higher in the SeHCAT-negative group whereas the SeHCAT-positive group attended more clinic appointments (p=0.013).Conclusion: A positive diagnosis of bile acid diarrhoea, made by a SeHCAT test, resulted in reduced use of diagnostic investigations over the subsequent five years.