Eighteen-year-old hair loss is serious, consider seborrheic alopecia, baldness, malnutrition caused by hair loss, mainly to strengthen the nutrition, medication, hair transplantation and other improvements. 1. Seborrheic alopecia: Seborrheic alopecia is related to heredity and is mainly caused by elevated androgen activity in the body. Men can take finasteride orally, women can use spironolactone, in the use of medication at the same time can be applied locally tincture of minoxidil, to promote hair growth, hair loss can also be controlled after hair transplantation. 2. Patch baldness: Patch baldness and heredity, mental stress, etc., mainly limited patchy hair loss, can be injected with glucocorticosteroids, such as betamethasone, trimethoprim, etc., in the use of medication at the same time can be applied locally tincture of minoxidil hair, if the effect of local medication is not obvious, but also can be taken orally cyclosporine, methotrexate. 3. malnutrition caused by hair loss: if excessive dieting, weight loss or some major diseases such as malignant tumors, can also cause malnutrition, hair loss, should be stopped to lose weight, strengthen the nutrition, if there is a major disease should be active primary disease. Eighteen-year-old hair loss is serious, there may be other reasons, it is recommended to go to the hospital in a timely manner, after the cause is clear standardized treatment, the above drugs should be used in accordance with the doctor’s instructions.