Temporary or permanent hair loss is called alopecia. Hair loss is a common side effect of chemotherapy or radiation therapy for cancer patients, second only to nausea and vomiting as a side effect of chemotherapy, and is often one of the biggest concerns and fears of chemotherapy for young patients. The cause of hair loss is related to damage to hair follicle cells by cytotoxic anticancer drugs or radiotherapy. The incidence of chemotherapy-induced alopecia and its extent depend on the type and dose of anticancer drugs, the duration of chemotherapy, and the combination of chemotherapy drugs used. Adriamycin, cyclophosphamide, isocyclophosphamide and pedialyte glycosides have the strongest alopecia, with an incidence of up to 80% or more, while other drugs such as cisplatin rarely occur. The higher the dose and the longer the duration of the drug, the greater the incidence and severity of alopecia. Hair loss is more common with multiple-drug combination chemotherapy than with single-drug chemotherapy. Other factors may also cause hair loss, such as gentamicin, minocycline, tetracycline, etc. in antimicrobial agents, anticoagulant drugs such as Zhabao and heparin, anticonvulsants, androgens (estrogens), aspirin, psoralen, allopurinol, etc. Abnormal body states may also cause hair loss, such as long-term high stress state, contact dermatitis, abnormal endocrine function, estrogen deficiency, herpes zoster, syphilis, malnutrition, etc. Hair loss caused by chemotherapy drugs is generally reversible and rarely permanent. Regrowth usually begins 1 to 2 months after stopping chemotherapy. Hair regrowth does not mean that chemotherapy is ineffective. Regenerated hairs sometimes change in color and structure, for example, the color may darken or lighten, the texture may become softer, and the hair often becomes curved and congenitally curly. There are no definite medications available for the prevention and treatment of hair loss. So, hair loss is not a scary thing. You just have to remember one thing: hair loss does not affect your life and work. Chemotherapy is acceptable, so what is not! Besides, most hair loss is temporary, and it will grow better later!