The goal of this single - center, prospective, randomized controlled study is to assess the therapeutic effects of five - flavor sophora flavescens enteric - coated capsules on radiation - induced proctitis in patients who have undergone pelvic radiotherapy. The main question it aims to answer is:

Does five - flavor sophora flavescens enteric - coated capsules treatment improve radiation - induced proctitis in these patients? Participants with radiation - induced proctitis following pelvic radiotherapy will be randomly allocated to either the trial group (receiving the capsules) or the control group (receiving conventional therapy). Assessments will be conducted to compare outcomes between the two groups.

Inclusion Criteria:

Aged 18 - 80 years. Undergoing pelvic radiotherapy with RTOG radiation - toxicity grade ≥2 and FOB (+) or fecal calprotectin Fc>150μg/g.

Absolute neutrophil count >1,500/μL, platelets >100,000/μL; AST <45U/L, ALT <40U/L; creatinine clearance >50ml/min.

Willing to sign consent and participate in required tests and follow - up.

Exclusion Criteria:

Previous pelvic/abdominal radiotherapy. Other severe intestinal diseases (e.g., Crohn's, ulcerative colitis, colorectal cancer).

Contraindications to five - flavor sophora flavescens enteric - coated capsules (e.g., prolonged QTc, hypokalemia, use of QTc - prolonging drugs, heart disease).

Allergy to the capsules or their components. Other therapies for radiation - induced proctitis (e.g., mesalamine, steroids, hyperbaric oxygen, laser therapy) in the past month.

Uncontrolled diseases that may affect the study, such as organ dysfunction, poorly controlled hypertension, coronary heart disease, arrhythmias, cerebrovascular disease, diabetes; myocardial infarction or heart failure in the past 6 months; jaundice due to hepatic insufficiency; AIDS; uncontrolled coagulation disorders.

Psychiatric patients unable to complete the study.