Taking Gefitinib for one year can generally have a therapeutic effect and may also produce side effects. Gefitinib is the name of a western medicine, it is an anti-tumor drug, used for the treatment of advanced metastatic non-small cell lung cancer, this product is mainly used for the treatment of advanced metastatic non-small cell lung cancer that has failed to receive previous chemotherapy, the proper use of medication will play a therapeutic role. Side effects: patients taking Gefitinib may have diarrhea, vomiting, nausea, elevated aminotransferase, elevated bilirubin, hepatitis, skin rash, itching, anorexia, fever, and other side effects, patients allergic to this tablet are prohibited, allergic people should be used with caution, and during the period of use of the drug should be regularly done to check the liver function and other related examinations, and the side effects are more serious should be stopped in time. Patients should use Gefitinib under the guidance of a physician’s consultation, if discomfort occurs during the use of medication, it is necessary to communicate with the doctor in a timely manner, according to the situation, in accordance with standardized treatment, do not be negligent, so as not to delay the condition.