Periods generally refer to menstruation. Taking tamoxifen for menstrual period is usually normal, but if the bleeding is heavy, you need to pay attention to it and seek medical attention if necessary. Tamoxifen Qi belongs to the antitumor drugs, but also non-steroidal anti-estrogen drugs. It is mainly used for the treatment of recurrent metastatic breast cancer in women, and can also be used as an adjuvant treatment for metastasis after breast cancer surgery to prevent recurrence of the disease. Tamoxifen will affect the secretion of estrogen to a certain extent, and there are adverse reactions such as menstrual disorders, so it is normal for patients to experience menstrual flow during the use of Tamoxifen. However, if the bleeding is heavy, it may be caused by vaginal bleeding, endometrial hyperplasia and other adverse reactions, which require timely consultation and relevant treatment by the doctor. During the process of medication, patients should strictly and closely observe the related side effects of the drug, once serious or persistent adverse reactions, such as hot flashes, nausea, skin rash, etc., need to consult the doctor in time. Patients with bone metastasis of breast cancer need to check blood calcium regularly in the early stage of treatment with tamoxifen. It should be used with caution in patients with abnormal liver function. In addition, patients should strictly follow the doctor’s instructions to take medication, not blindly self-use or arbitrarily increase or decrease the dosage of the drug, and pay attention to the diet to avoid spicy, stimulating food, so as not to cause discomfort and aggravate the disease.