Usefulness of Transanal Irrigation and Colon Hydrotherapy in the Treatment of Chronic Constipation and Beyond: A Review with New Perspectives for Bio-Integrated Medicine

Transanal Irrigation (TAI) and Colon Hydrotherapy (CHT) represent emerging therapeutic options that may complement first-line interventions or serve as rescue treatments for chronic constipation and fecal incontinence. Their clinical utility depends on patient characteristics, specific therapeutic goals, device features, and probe type, as well as the procedural setting. This review presents the various pathophysiological contexts in which these techniques can be applied, analyzing their specific characteristics and potential pros and cons. Moreover, these interventions are also considered within a Psycho-Neuro-Endocrino-Immunological (PNEI) framework, given the potential influence of intestinal function and microbiota modulation on the bidirectional communication pathways linking the enteric nervous system, neuroendocrine regulation, immune activity, and global patient well-being. Since there is not yet enough scientific data on this topic, future research should prioritize randomized controlled trials comparing these techniques with other standard treatments (e.g., laxatives or dietary fiber) in defined patient populations. Longitudinal studies will also be essential to clarify long-term safety, potential effects on microbiota, and both risks and benefits. Standardization of technical procedures also remains a critical need, especially regarding professional competencies, operating parameters (e.g., instilled volumes and pressure ranges), and reproducible protocols. Moreover, future investigations should incorporate objective outcome measures, as colonic transit time, stool form and frequency, indices of inflammation or intestinal wall integrity, and changes to microbiome composition. In conclusion, TAI and CHT have the potential to serve as important interventions for the treatment and prevention of chronic constipation and intestinal dysbiosis, as well as their broader systemic correlates, in the setting of bio-integrated medicine.