Sudden weakness of the legs and inability to stand up may be related to lower limb fatigue, hypoglycemia, electrolyte disorders, lumbar disc herniation, stroke, acute myelitis, Guillain-Barre syndrome, myasthenia gravis, and other factors. It is recommended to consult a doctor in a timely manner to clarify the cause and then carry out treatment. 1, lower limb fatigue: when strenuous exercise can lead to excessive fatigue of the lower limbs, resulting in a sudden weakness of the legs, can not stand up, usually after appropriate rest symptoms can be alleviated; 2, hypoglycemia: hypoglycemic people can appear dizziness, nausea and other symptoms, but also a sudden weakness of the legs, can not stand up phenomenon, you can take candy and other The symptoms can be relieved faster by taking candy and other foods with high sugar content to replenish sugar; 3, electrolyte disorders: for example, insufficient intake or excessive loss of potassium can lead to weakness, weak legs, can not stand up, can be accompanied by vomiting, nausea, dizziness and other symptoms, can be relieved by taking potassium chloride extended-release tablets and other drugs; 4, lumbar disc herniation: lumbar disc herniation can compress the nerves in the lower limbs, leading to back pain, lumbar pain, leg weakness, Lumbar pain, leg weakness, and inability to stand up can be treated by traction, acupuncture, massage, etc.; 5, stroke: stroke can cause symptoms such as numbness of the partial body, headache, vomiting, and impaired consciousness, and can also lead to sudden weakness of the thighs and inability to stand up, which can be treated by taking drugs such as atorvastatin calcium, aspirin, and if necessary, carotid endarterectomy; 6, acute myelitis: acute myelitis can be treated by taking drugs such as atorvastatin calcium, aspirin, and if necessary, carotid endarterectomy; 6 Acute myelitis: Acute myelitis can lead to movement disorders, so that muscle tone gradually increases, resulting in weak legs and inability to stand up, which can be accompanied by symptoms such as hypothermia and numbness of the limbs, and can be treated by taking vitamin B1 tablets, methylcobalamin and other drugs to help restore neurological function; 7. Green-Barre syndrome: Green-Barre syndrome can be caused by infection, autoimmune and other factors, which can result in symmetrical limb Weakness, dyspnea and other symptoms, manifesting as sudden weakness of legs and inability to stand up, which can be relieved by taking vitamin drugs and so on; 8, myasthenia gravis: myasthenia gravis can make the patient’s muscles weak, with sudden weakness of legs and inability to stand up, which can be treated by taking cholinesterase inhibitors such as neostigmine methosulfate.