Mannitol plus dexamethasone can relieve a range of clinical symptoms caused by lumbar disc herniation. Lumbar disc herniation is more common in clinical practice. When a lumbar disc herniation is severe and presses on the nerves, pain, numbness and weakness in the lower extremities can occur. Dexamethasone is a commonly used hormonal drug that can fight against sterile inflammation, slow down the release of inflammatory factors, relieve symptoms caused by local sterile inflammation, relieve nerve root edema and eliminate local sterile inflammation. Mannitol is a commonly used drug in orthopedics and neurosurgery, which can alleviate the edema of nerve tissues through hypertonicity and play a better role in reducing swelling. In patients with severe symptoms in the acute stage of lumbar disc herniation, the combined use of mannitol plus dexamethasone can alleviate the phenomenon of nerve compression and edema caused by lumbar disc herniation or spinal cord injury, and also improve the patient’s low back and leg pain. However, it should be noted that dexamethasone belongs to the hormone class of drugs, mannitol and dexamethasone combined medication, pay attention not to overdose, the use of the cycle should not be too long. Specific medication should follow the doctor’s instructions, should avoid blind self-medication.