Methylcobalamin can treat peripheral neuropathy, which is clearly indicated in the instructions of methylcobalamin, and can also treat megaloblastic anemia caused by vitamin B12 deficiency. Methylcobalamin is mainly endogenous vitamin B12, which exists in blood and bone marrow fluid. Compared with vitamin B12, methylcobalamin has a good effect on neuronal conduction and can promote the metabolism of nucleic acid, protein and fat through methyl conversion reaction. It acts as a coenzyme of methionine synthase, which can induce the conversion of homocysteine to methionine, participate in the process of deoxynucleoside synthesis of thymine, promote nucleic acid and protein synthesis, and thus can promote intra-axonal transport and axonal regeneration, as well as the formation of nerve axons, and also prevent the degeneration of axons, thus repairing the damaged nerve tissue. This drug can reach peak blood oxygen concentration in three hours of oral administration. It is absorption and dose dependent, in other words, a normal larger dose may be relatively effective, and methylcobalamin can be detected at once from blood, adrenal glands, liver, stomach and other tissues in high concentrations. When peripheral neuropathy is identified, methylcobalamin can be administered for treatment.