Common causes of diseases that cause hair loss include androgenetic alopecia, baldness, malnutrition, and hypothyroidism. Hair loss caused by different diseases can be improved by medication or dietary adjustment. 1. Androgenetic alopecia: androgen is one of the important mechanisms for the development of this disease. Men can take the anti-sex hormone drug finasteride orally, women can take spironolactone orally, and the hair growth drug minoxidil can also be used externally. 2. Patch baldness: Patch baldness is a psychogenic factor-led, autoimmune-related non-scarring hair loss disease, can be used externally Minoxidil solution, 10% chili tincture, etc., baldness can be used externally or injected glucocorticoids to reduce perifollicular inflammation such as compound betamethasone, etc., to treat the hair growth. 3. Malnutrition: If the patient to malnutrition lead to hair loss need to supplement high protein food to improve. 4. Hypothyroidism: Hypothyroidism can lead to thinning and drying of hair, which can be treated with drugs such as levothyroxine. Hair loss patients are recommended to consult a doctor in time, under the guidance of the doctor to choose the appropriate medication to treat hair loss, do not self-medication!