Products
Methylene blue (ATC V03AB17, ATC V04CG05) is commercially available in the form of eye drops (collyre bleu + naphazoline). It has been approved in many countries since 1984. In 2020, a solution for injection was registered as an antidote (methylthioninium chloride Proveblue from Bichsel).
Structure and properties
Methylene blue or methylthioninium chloride (C16H18ClN3S – xH2O, Mr = 319.9 g/mol) is a phenothiazine derivative. It exists as a dark blue crystalline powder with a copper luster or as green crystals with a bronze luster and is readily soluble in water. Aqueous solutions have a blue color.
Effects
Methylene blue has antiseptic properties.
Indications
Methylene blue is approved in many countries for the treatment of nonspecific conjunctivitis and as a disinfectant against fish diseases in freshwater ornamental fish. It is further used as a dye, reagent and antidote (methemoglobinemia).
