Letrozole two tablets a day is not allowed, patients need to strictly follow the doctor’s instructions. Letrozole in the clinic is mainly used for postmenopausal patients with early breast cancer adjuvant therapy, can also be used to receive tamoxifen adjuvant therapy for five years, and can also be used for postmenopausal, estrogen and progesterone receptor-positive or receptor status of the patients with advanced breast cancer, and such patients need to be for the natural menopause or artificially induced menopause. The size of the drug is usually 2.5mg/tablet, and patients need to take 2.5mg once a day, which is 1 tablet. Therefore, taking 2 tablets in 1 day is beyond the normal dosage of the drug. Patients may experience adverse reactions such as hair loss, excessive sweating, erythema, depression, and appetite changes after taking the drug. However, there is no clear clinical data and research on drug overdose. It is recommended that patients take Letrozole in strict compliance with the doctor’s instructions, and read the instructions carefully before using the drug to understand its dosage and avoid unauthorized use of the drug, so as not to cause unnecessary damage to the organism.