Methylene Blue
Phenothiazine dye + electron-cycling agent. FDA-approved IV antidote for methemoglobinemia. Off-label uses span mitochondrial-energy + cognitive-enhancement protocols at controversial sub-therapeutic doses.
MB acts as electron donor + acceptor in the mitochondrial electron transport chain (donates to complex IV / cytochrome c oxidase). Approved IV indication is severe methemoglobinemia at 1-2 mg/kg. Off-label cognitive-enhancement cohort uses sub-therapeutic oral doses (0.5-4 mg/day) based on rodent neuroprotection literature + Bryan Johnson protocol popularization. The leap from rodent model to oral microdose efficacy in healthy humans is inadequately validated. Stack catalogs MB for SAFETY interaction surface — serotonin syndrome with SSRIs is the real risk users encounter.
Distilled themes from named communities — Reddit threads, forums, creator commentary. Not direct quotes; not clinical evidence. Useful for calibrating expectations against what real self-experimenters report.
Cohort splits sharply: Bryan Johnson DD followers report subjective cognitive lift at 2-4 mg oral; mainstream-medicine cohort points to inadequate human evidence + serotonin syndrome risk. Stack documents both honestly + flags the SSRI interaction explicitly.
HARD CONTRAINDICATION — concurrent SSRIs / SNRIs / MAOIs / TCAs (serotonin syndrome can be fatal; FDA boxed warning 2011). G6PD deficiency = hard contraindication (hemolysis). Stains everything blue — urine, sweat, contact lenses. Pharmaceutical-grade USP MB only — industrial / aquarium-grade contains heavy metals. Bryan Johnson popularization has driven dosing-creep + casual self-experimentation; the cognitive-enhancement evidence base does NOT support this.
External links to PubMed searches, ClinicalTrials.gov, and FDA materials. We do not host papers — we point at canonical sources.
- RegulatoryENREGULATORYNIH-fundedVerified 3d agoFDA — Methylene Blue serotonin-syndrome boxed warning (2011)
- PubMedENREVIEWAcademic-fundedVerified 3d agoRojas JC et al. — Methylene blue neuroprotection rodent literature (Prog Neurobiol 2012)
- PubMedENRCTAcademic-fundedVerified 3d agoTelch MJ et al. — Methylene blue + extinction memory consolidation human RCT (J Psychiatr Res 2014)
FDA-approved IV (methemoglobinemia, cyanide poisoning adjunct). Oral form sold as compounded prep or USP-grade powder; off-label cognitive use lacks FDA endorsement.