methylene blue

Methylene blue is a synthetic heterocyclic aromatic compound used primarily as an oxidation-reduction agent in medicine. Its main FDA-approved indication is the treatment of acquired methemoglobinemia in both adults and children. Methemoglobinemia is a condition where hemoglobin cannot effectively deliver oxygen to tissues due to oxidation of iron within hemoglobin from the ferrous (Fe2+) to ferric (Fe3+) state. Methylene blue acts by being reduced within red blood cells to leucomethylene blue via NADPH-dependent pathways; this reduced form then converts methemoglobin back into functional hemoglobin[1][4][5]. Beyond its primary use for methemoglobinemia (including that caused by drugs such as dapsone or certain anesthetics), methylene blue has been investigated for other indications such as vasoplegic syndrome and neurodegenerative diseases like Alzheimer's disease due to its inhibition of nitric oxide synthase and guanylate cyclase and potential effects on tau protein aggregation[4][6]. It also possesses monoamine oxidase inhibitory activity at higher concentrations[6].

Brand names

ProvayblueProveblueHyophenPhosphasalUrelleUribelUrimar Reformulated Oct 2013Urin DSUrogesic Blue Reformulated Apr 2012Ustell

Other names

methylthioninium chloride