Chemicals and Drugs

Methylene Blue

A compound consisting of dark green crystals or crystalline powder, having a bronze-like luster. Solutions in water or alcohol have a deep blue color. Methylene blue is used as a bacteriologic stain and as an indicator. It inhibits GUANYLATE CYCLASE, and has been used to treat cyanide poisoning and to lower levels of METHEMOGLOBIN.

National Library of MedicineMedical Subject Headings2026

Structured Summary

Abstract

A compound consisting of dark green crystals or crystalline powder, having a bronze-like luster. Solutions in water or alcohol have a deep blue color. Methylene blue is used as a bacteriologic stain and as an indicator. It inhibits GUANYLATE CYCLASE, and has been used to treat cyanide poisoning and to lower levels of METHEMOGLOBIN.

Chemical Identity

Chemical Information

Molecular Formula
C16H18ClN3S
Molecular Weight
319.9 g/mol
CAS Registry No.
61-73-4
IUPAC Name
[7-(dimethylamino)phenothiazin-3-ylidene]-dimethylazanium chloride
InChIKey
CXKWCBBOMKCUKX-UHFFFAOYSA-M
SMILES
CN(C)C1=CC2=C(C=C1)N=C3C=CC(=[N+](C)C)C=C3S2.[Cl-]
MeSH Unique ID
D008751
Source
PubChem CID 6099

MeSH Record

Classification

Broader headings

Related Concepts

Knowledge Graph

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Drug Class

Pharmacological Action

MeSH Record

Synonyms

12 entry terms
  • Basic Blue 9
  • Methylene Blue N
  • Methylthionine Chloride
  • Methylthioninium Chloride
  • Swiss Blue
  • Blue 9, Basic
  • Blue N, Methylene
  • Blue, Methylene
  • Blue, Swiss
  • Chromosmon
  • Urolene Blue
  • Blue, Urolene

MeSH Record

Aspects Covered

19 allowable subheadings

Indexed with the subheadings administration & dosage, adverse effects, analogs & derivatives, analysis, chemical synthesis, chemistry, classification, economics, history, isolation & purification, metabolism, pharmacokinetics, pharmacology, poisoning, radiation effects, standards, supply & distribution, therapeutic use, toxicity.

MeSH Hierarchy

Tree Numbers

AMA Style

References

  1. National Library of Medicine. Methylene Blue. Medical Subject Headings (MeSH). 2026. Unique ID D008751. http://id.nlm.nih.gov/mesh/2026/D008751
  2. Methylene Blue. In: Wikipedia. https://en.wikipedia.org/wiki/Methylene_blue
  3. Methylene Blue. In: Wikidata. https://www.wikidata.org/wiki/Q422134
  4. Methylene Blue. In: PubChem Compound. CID 6099. https://pubchem.ncbi.nlm.nih.gov/compound/6099