Methylene blue

Methylene blue
INN: Methylthioninium chloride
Molecular structure
A volumetric flask of a methylene blue solution
Clinical data
Trade namesUrelene blue, Provayblue, Proveblue, others
Other namesCI 52015, basic blue 9
AHFS/Drugs.comMonograph
License data
Pregnancy
category
  • AU: D
Routes of
administration
By mouth, intravenous
ATC code
Legal status
Legal status
Pharmacokinetic data
Elimination half-life5–24 hours (IVTooltip intravenous therapy)
ExcretionRenal
In rats: 18%(POTooltip Oral administration), 28% (IV)
Identifiers
  • 3,7-bis(Dimethylamino)-phenothiazin-5-ium chloride
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.000.469
Chemical and physical data
FormulaC16H18ClN3S
Molar mass319.85 g·mol−1
3D model (JSmol)
  • CN(C)c1ccc2c(c1)sc-3cc(=[N+](C)C)ccc3n2.[Cl-]
  • InChI=1S/C16H18N3S.ClH/c1-18(2)11-5-7-13-15(9-11)20-16-10-12(19(3)4)6-8-14(16)17-13;/h5-10H,1-4H3;1H/q+1;/p-1 Y
  • Key:CXKWCBBOMKCUKX-UHFFFAOYSA-M Y
  (verify)

Methylthioninium chloride, commonly called methylene blue, is a salt used as a dye and as a medication. As a medication, it is mainly used to treat methemoglobinemia. It has previously been used for treating cyanide poisoning and urinary tract infections, but this use is no longer recommended.

Methylene blue is typically given by injection into a vein. Common side effects include headache, nausea, and vomiting.

Methylene blue was first prepared in 1876, by Heinrich Caro. It is on the World Health Organization's List of Essential Medicines.