BACKGROUND: Retrograde colonic irrigation is a possible treatment for defaecation disorders when conservative treatment or surgery has failed. The aim of this prospective study was to investigate its effectiveness. METHODS: Patients were divided into three groups: those with faecal incontinence (A), constipation (B) or both (C). The Biotrol Irrimatic pump or the irrigation bag was used for colonic irrigation. Patients completed a questionnaire at baseline and after 3, 6 and 12 months, as well as a Short Form 36 health survey and an American Society of Colon and Rectal Surgery quality of life questionnaire at baseline and after 6 months. RESULTS: The study included 39 patients (26 women; mean age 58.0 years). In group A, 11 of 18 patients were pseudocontinent for faeces at 3 months (P < 0.001). Parks' incontinence scores decreased for all patients in this group at 3 months (P < 0.001), 6 months (P = 0.036) and 1 year (P = 0.005). In group B, three of ten patients reported a major improvement. The mean score for the feeling of incomplete evacuation decreased at 3 months (P = 0.007), 6 months (P = 0.013) and 1 year (P = 0.036). In group C, six of ten patients became pseudocontinent for faeces (P = 0.009) and three reported improvement in constipation. The overall quality of life scores improved (P = 0.012). CONCLUSION: Retrograde colonic irrigation is an undervalued but effective alternative treatment for intractable defaecation disorders.