Radiation Enteritis: Acute vs. Chronic Symptoms, Treatment Options, and Prevention During Planning

Radiation enteritis is inflammation of the small intestine caused by radiation therapy to the abdomen or pelvis. It can be acute (during/weeks after) or chronic (months–years later).

Symptoms

• Abdominal cramping, pain
• Nausea, vomiting
• Diarrhea (often watery, urgent)
• Weight loss, malnutrition
• Fatigue, anemia (chronic blood loss)
• Obstruction, fistula, perforation (severe chronic)

Treatment

• Acute: Loperamide, antispasmodics, hydration, low-residue diet, probiotics, 5-ASA enemas (distal).
• Chronic: Nutritional support (elemental diets, TPN), stricture dilation/stenting, surgery (strictureplasty, resection) for obstruction/fistula; hyperbaric oxygen for refractory radiation proctitis.

Prevention (During RT Planning)

• IMRT/VMAT to minimize bowel volume receiving high dose
• Prone positioning, belly board, bladder filling protocols
• Spacers (hydrogel) to displace bowel from prostate/rectum target
• Dose constraints: V45 <195 cc, V50 <100 cc (small bowel)

Early recognition and multidisciplinary management (radiation oncology, gastroenterology, nutrition, surgery) optimize quality of life.