It is possible to cause abdominal pain during gefitinib administration. Gefitinib is classified as a targeted agent for the first-line treatment of patients with locally advanced or metastatic non-small cell lung cancer with sensitive mutations in the epidermal growth factor receptor gene. During the administration of the drug, patients may experience adverse reactions such as pancreatitis as well as perforation of the digestive tract, which can cause irritation of the surrounding tissues and lead to the development of abdominal pain. In addition to abdominal pain, other adverse reactions include symptoms such as nausea, diarrhea, dry mouth, conjunctivitis, bleeding, abnormal liver and kidney function, and rash. Gefitinib contraindications: contraindicated in children, puberty, pregnancy and lactation: contraindicated in those with significant interstitial lung fibrosis, severe abnormalities of liver and renal function; used with caution in the elderly; contraindicated in those who are allergic to the product. Once obvious abdominal pain, abnormal liver and kidney function, abnormal visual status, obvious bleeding tendency and generalized multiple skin rashes occur during the use of the drug, it is necessary to consult a doctor in time and carry out standardized treatment under the guidance of clinicians.