Late onset bowel dysfunction post-pelvic radiotherapy is an increasingly common clinical scenario which is related to improved oncological treatments and cancer survival. 50% of patients develop bowel symptoms after pelvic radiotherapy which affects quality of life. Historically, bowel symptoms post-pelvic radiotherapy have been labelled 'chronic radiation proctitis', although it is increasingly recognised that these symptoms are due to dysfunction of the gastrointestinal (GI) tract at numerous points. The evidence-base is poor and comprises often small, heterogenous, single centre unblinded studies. This article critically reviews the evidence for the medical treatment options for 'chronic radiation proctitis', which include anti-inflammatory drugs, antibiotics, sucralfate, formalin and hyperbaric oxygen. The difficulties in extrapolation from the literature to clinical practise are also explored. From the available evidence, rectal sucralfate appears to have greater efficacy than anti-inflammatory agents, which are more effective if used with oral metronidazole. Furthermore, hyperbaric oxygen is emerging as promising treatment for radiation toxicity. However, bowel dysfunction post-pelvic radiotherapy is a complex clinical condition which reflects multi-site GI tract pathologies both related and unrelated to previous oncological treatments. From this review article a clear need for an adjustment to both diagnosis and treatment of these patients, as well as for further research, emerges.