The difference between cytarabine sodium tablets and methylcobalamin tablets mainly includes different action mechanisms and different therapeutic indications. 1. Different mechanism of action: cytarabine sodium tablets can reduce cerebral vascular resistance, increase cerebral blood flow and promote substance metabolism, improve cerebral circulation. Mecobalamin tablets can easily enter neuronal cells, participate in the synthesis of brain cells and spinal cord neurons, and promote the utilization of folic acid and nucleic acid metabolism. 2. Different therapeutic indications: cytarabine sodium tablets are mainly used for the treatment of neurological sequelae caused by craniocerebral injury or cerebrovascular accident. Methylcobalamin tablets are used for the treatment of peripheral neuropathy such as polyneuritis, trigeminal neuralgia and multiple cerebral nerve damage. Specific drugs should be used correctly under the guidance of a doctor to avoid adverse reactions to self medication.