Methylene blue

Not to be confused with methyl blue, new methylene blue, or methyl violet.
Methylene blue
Molecular structure
A volumetric flask of a methylene blue solution
Clinical data
Trade namesUrelene blue, Provayblue, Proveblue, others[1][2]
Other namesCI 52015, basic blue 9[3]
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 to 24 hours[6]
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 Edit this at Wikidata
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 checkY
  • Key:CXKWCBBOMKCUKX-UHFFFAOYSA-M checkY
  (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 by chemically reducing the ferric iron in hemoglobin to ferrous iron.[6][2] Specifically, it is used to treat methemoglobin levels that are greater than 30% or in which there are symptoms despite oxygen therapy.[2] It has previously been used for treating cyanide poisoning and urinary tract infections, but this use is no longer recommended.[6]

Methylene blue is typically given by injection into a vein.[6] Common side effects include headache and vomiting. While use during pregnancy may harm the fetus, not using it in methemoglobinemia is likely more dangerous.[6][2]

Methylene blue was first prepared in 1876, by Heinrich Caro.[9] It is on the World Health Organization's List of Essential Medicines.[10]

  1. ^ Hamilton R (2015). Tarascon Pocket Pharmacopoeia 2015 Deluxe Lab-Coat Edition. Jones & Bartlett Learning. p. 471. ISBN 9781284057560.
  2. ^ a b c d British national formulary : BNF 69 (69 ed.). British Medical Association. 2015. p. 34. ISBN 9780857111562.
  3. ^ Lillie RD (1977). H. J. Conn's Biological stains (9th ed.). Baltimore: Williams & Wilkins. pp. 692p.
  4. ^ "FDA-sourced list of all drugs with black box warnings (Use Download Full Results and View Query links.)". nctr-crs.fda.gov. FDA. Retrieved 22 Oct 2023.
  5. ^ "Provayblue- methylene blue injection". DailyMed. 29 June 2022. Retrieved 4 March 2023.
  6. ^ a b c d e f "Methylene Blue". The American Society of Health-System Pharmacists. Archived from the original on 10 May 2017. Retrieved 8 January 2017.
  7. ^ "Lumeblue EPAR". European Medicines Agency. 19 June 2020. Retrieved 4 March 2023.
  8. ^ "Lumeblue Product information". Union Register of medicinal products. Retrieved 3 March 2023.
  9. ^ Ahmad I, Aqil F (2008). New Strategies Combating Bacterial Infection. John Wiley & Sons. p. 91. ISBN 9783527622948. Archived from the original on 2017-09-18.
  10. ^ World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization. hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.