Methylene Blue,
methylthionine chloride or
3,7-bis(dimethylamino)phenothiazin-5-ium chloride is a
chemical compound used as a
dye and medication for
Gram's stain,
Wright stain[?], and the treatment of metoxyhemoglobinemia.
Its molecular formula is C16H18ClN3S.
Its CAS number is 61-73-4: its EC number is 200-515-2 .