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Provayblue (methylthioninium chloride)

FDA-approved active Quality 62/100

Provayblue works by inhibiting the enzyme amine oxidase [flavin-containing] A, which is involved in the breakdown of certain amines in the body.

At a glance

Generic namemethylthioninium chloride
Drug classMonoamine Oxidase Inhibitors
TargetAmine oxidase [flavin-containing] A
Therapeutic areaRare Disease
PhaseFDA-approved

Mechanism of action

Methylene blue is water soluble thiazine dye that promotes non-enzymatic redox conversion of metHb to hemoglobin. In situ, methylene blue is first converted to leucomethylene blue (LMB) via NADPH reductase. It is the LMB molecule which then reduces the ferric iron of metHb to the ferrous state of normal hemoglobin.

Approved indications

Boxed warnings

Common side effects

Drug interactions

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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