Post-chemotherapy gastrointestinal reaction grading is based on the severity of gastrointestinal reactions, such as constipation, diarrhea, nausea, and vomiting, which are generally divided into 5 grades. Grade 1: constipation: occasional or intermittent; diarrhea: increased frequency of stools, <4 increases per day/mild increase in bowel movements; nausea: decreased appetite; vomiting: no intervention required. Grade 2: Constipation: persistent symptoms, regular use of laxatives or enemas; diarrhea: increase in number of bowel movements 4-6 times per day/moderate increase in bowel movements; nausea: decrease in oral intake, no significant weight loss; vomiting: need for intravenous fluid replacement. Grade 3: Constipation: stubborn constipation requiring manual evacuation; Diarrhea: increase ≥7 times per day/severe increase in bowel movements requiring hospitalization; Nausea: insufficient oral intake requiring nasal feeding or parenteral nutrition; Vomiting: tube feeding required, hospitalization for parenteral nutrition. Grade 4: constipation, diarrhea, nausea, and vomiting are life-threatening and require emergency treatment. Grade 5: Death.