Methylene Blue

MitochondrialCognitionExperimental

An old dye repurposed as a mitochondrial-electron carrier. Improves cellular oxygen utilisation; turns urine and tongue blue. Take very seriously and at low dose.

EvidenceEmerging

Strong mechanism evidence. Small human trials support cognitive benefit, antidepressant effect, and possible Alzheimer's slowing. Larger trials underway. Effects: hours to weeks.

Methylene blue is a phenothiazine dye in clinical use since 1891 — originally as a malaria treatment, then as an antidote for methemoglobinemia. It acts as an alternative electron carrier in the mitochondrial respiratory chain, improving ATP production when oxygen delivery is impaired. At low doses (0.5–4 mg/kg) it shows cognitive enhancement, antidepressant effects, and protection against neurodegeneration in trials. At high doses it does the opposite (paradoxical effect). Pharmaceutical-grade only — aquarium / textile-grade methylene blue contains contaminants. Significant interaction risk with SSRIs (serotonin syndrome).

Form: Pharmaceutical / USP-grade methylene blue only. Liquid or capsules. Avoid aquarium / fabric / lab-grade.
Dose: Very low: 0.5–4 mg/day (microdose). Some studies go to 0.5 mg/kg. The dose-response curve is U-shaped — more is not better.
Timing: AM. Mildly activating. Stains everything blue — including tongue, urine.
Schedule: Daily or cycled (2–3 days/week).
Side effects: Blue urine, blue tongue (cosmetic, harmless). Headache, GI upset, sweating. Hemolysis in G6PD deficiency.
Interactions: SSRIs, SNRIs, MAOIs, tramadol, triptans — serotonin syndrome risk is real and serious. Methylene blue is itself a potent MAOI. Do not combine.
Contraindications: On any serotonergic medication (most antidepressants, migraine triptans, tramadol). G6PD deficiency. Pregnancy / breastfeeding. Severe kidney impairment.
Lab markers: Not standard.
Food sources: Not food.

Pairs with

Red / near-infrared light (synergistic photobiomodulation effect — Gonzalez-Lima lab). NMN / NR (mitochondrial support). CoQ10, PQQ.

within Coenzymes & mitochondrial cofactors