Although pelvic radiotherapy, either alone or combined with chemotherapy, has proved to be successful in the treatment of patients with rectal, gynecological and urologic cancer, it is not devoid of side effects. Among patients receiving pelvic radiotherapy more than 70% develop acute inflammatory changes causing gastrointestinal symptoms during treatment. The most frequently reported symptom related to radiation-induced intestinal mucositis is diarrhoea. Among nutritional interventions used to manage radiation-induced diarrhoea, probiotics has gained popularity. This term describes organisms and substances that improve microbial balance in the intestines. Although encouraging results have been obtained in clinical trials, the potential of oral probiotics to manage gastrointestinal symptoms needs further research. The article also outlines recent patents related to probiotics therapy to reduce radiation induced mocositis.