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Methylene blue

Aliases: Methylene Blue · Methylthioninium chloride

Last verified: 2026-09-23

Approved drugStrong evidenceSmall moleculesMedium interest

The short version

An old drug/dye (methemoglobinemia, historically malaria) — micro-dosed as a mitochondrial nootropic: improves cellular respiration and memory in small studies.

Identity & type

Molecular type
mali molekul
Origin
An old drug/dye (methemoglobinemia, historically malaria) — micro-dosed as a mitochondrial nootropic: improves cellular respiration and memory in small studies.

Mechanism of action

Redox mediator in the ETC (bypasses complex I/III dysfunction); MAO-A inhibition at higher doses; anti-tau aggregation (preclinical).

Dosing & routes

Official / clinical context

Approved drug — indications, dosing and warnings are defined by the official label. Nootropic: 0.5–4 mg/kg (USP grade), usually 5–50 mg/day.

Regulator-approved labeling and published study designs — never a recommendation.

Community-reported practice

Nootropic: 0.5–4 mg/kg (USP grade), usually 5–50 mg/day. Micro-dosing: clearer thinking, energy and an "antidepressant" tone in part of the community; blue urine confirms absorption. Strictly avoided with SSRIs.

Unverified self-reports. Not medical advice. Not endorsement.

Expected effects (community)

Micro-dosing: clearer thinking, energy and an "antidepressant" tone in part of the community; blue urine confirms absorption. Strictly avoided with SSRIs.

Protocol — official vs community

Official / label

Approved (ProvayBlue) for methemoglobinemia: 1–2 mg/kg IV. Cognitive/mitochondrial dosing is off-label and unstandardized.

  1. 01Off-label oral use: 0.5–4 mg/kg studies

Duration: Indication-defined.

MAO-A inhibitor at higher doses and serotonin-toxicity risk with serotonergic drugs — the interaction that matters most.

Community (anecdotal)

0.5–1 mg/kg oral (often 10–50 mg) morning for cognitive/mitochondrial purposes.

Cycle:
Continuous or pre-cognitive-demand dosing.
Break:
None standardized.

SSRIs are the hard no-combination; blue urine is the harmless signature.

Human evidence

Small fMRI memory studies; tau program (LMTX) Phase III — negative as a drug, but research continues.

Preclinical evidence

The preclinical phase was completed and submitted to regulators as part of registration; pharmacology and toxicology details are part of the official label.

Known risks

  • Blue urine/stool; serotonin-syndrome risk with SSRIs; dangerous in G6PD deficiency.characterized

Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.

Unknowns & evidence gaps

  • Real-world data outside controlled trials

Frequently asked questions

References