Intravenous injection of mannitol for lumbar disc herniation mainly plays the role of eliminating nerve root edema, that is, the role of dehydration, allowing nerve root congestion and edema to dehydrate, which can also reduce nerve root compression and nerve root edema, thus reducing symptoms and avoiding irreversible damage caused by long-term nerve root compression or edema, which is a more common treatment method in clinical practice. Mannitol injection therapy also requires certain indications, for example, patients with diabetes should not be used. At the same time, mannitol treatment is only symptomatic treatment, and does not remove the cause of the disease. Detailed examination in the hospital, after a clear diagnosis, should be treated according to the cause of the disease, including surgery.