Pyrrolitinib is administered in cycles of 21 days and is usually used for 2-8 courses of treatment or taken until conditions such as drug resistance as well as serious adverse reactions occur. Pyrrolitinib tablets are an antineoplastic agent indicated in combination with capecitabine for the treatment of patients with recurrent or metastatic breast cancer who are epidermal growth factor receptor 2 (HER2)-positive and have not previously received or received trastuzumab. Patients should have received oncolytic or paclitaxel chemotherapy prior to using this product. Common side effects of this drug include gastrointestinal reactions, abnormal liver function, bone marrow suppression, etc. It is contraindicated for those who are allergic to the ingredients of this drug and should be used under the guidance of a medical professional. Piretinib is usually administered every 21 days as a cycle, and the specific duration of the medication depends on the condition of the patient and the effect of the drug, and usually 2 to 8 courses of treatment are administered. When patients develop drug resistance, or when serious adverse reactions occur, they should consult their doctor in time and stop the drug under the doctor’s guidance. The above drugs need to be used in a standardized manner under the guidance of a doctor to avoid adverse consequences.