Proctitis is an inflammation that occurs in the mucosa of the rectum. Typical symptoms include abdominal pain, diarrhea, a feeling of heaviness around the anus, and urgency followed by a sensation of incomplete evacuation. More severe inflammation can also lead to the presence of mucus and bloody pus in the stool. Bleeding from the rectum is another typical symptom, with the amount of bleeding related to the severity of the inflammation. Severe inflammation can directly cause pain in the anus and rectum. Abdominal pain and diarrhea may alternate, and long-term proctitis can also lead to loss of appetite, weight loss, fever, nausea, and vomiting. It is necessary to promptly perform a colonoscopy to understand the severity of the lesions and actively provide symptomatic treatment.