(UroToday.com) Radiation toxicity is defined as the transient or long-term sequelae to normal tissues due to pelvic radiotherapy. The most common pelvic radiation toxicity is gastrointestinal, and it is estimated that 10-20% of patients may develop GI toxicities over a ten-year period following pelvic radiation. Diarrhea, bleeding, and incontinence are the most common GI toxicities, with their severity depending on the radiation regimen and area irradiated. Acute toxicity is defined as within the first three months, whereas chronic toxicity is after the three-month time point. Risk factors for developing late GI toxicity include diabetes, inflammatory bowel disease, low BMI, collagen vascular disease, prior surgery, HIV, chemotherapy, tobacco use. While there are several therapies for the management of the side effects of pelvic radiation, they are often under-used, sometimes because late toxicities are under-recognized. The mechanism whereby late radiotherapy toxicity emerges is thought to be more related to ischemic changes in small vessels, which may explain why anti-inflammatory medications are less effective in late toxicity.