The raw compendium. No fluff. Only vetted signal.

Methylene blue is a century-old pharmaceutical dye with a rare trick: at low dose it acts as an accessory electron carrier, taking electrons from NADH and handing them to cytochrome c — a chemical bypass around a stalled mitochondrial chain that raises brain oxygen use, glucose uptake, and blood flow. One small randomized human fMRI trial found a ~7% gain in memory retrieval on a low oral dose. The mechanism is elegant and the signal is real — but everything here is gated by safety. Methylene blue is a potent MAO-A inhibitor that can trigger fatal serotonin toxicity with SSRIs; it follows a hormetic U-curve where high dose flips pro-oxidant; and it demands pharmaceutical (USP) grade, because industrial and aquarium versions carry contaminants. A brilliant bioenergetic lever with a knife-edge of dose, purity, and drug interactions.

• ›USP / pharmaceutical grade only. Aquarium and industrial methylene blue is not the same product — it can carry heavy-metal and dye contaminants and is not fit for human use.
• ›Contraindicated with serotonergic drugs (SSRIs, SNRIs, MAOIs, some pain/migraine meds). The MAO-A inhibition can trigger serotonin toxicity — this is the line that can kill.
• ›Low dose is the entire point. The benefit lives in a narrow milligram window; more is not better — it flips pro-oxidant. Physician oversight and drug-interaction screening are mandatory.

For a cognitively demanding operator, methylene blue is a mechanistically elegant bioenergetic lever with a real — if small — human signal. But the calibrated read is a gated Tier-B tool, not a casual supplement: it sits behind a potentially fatal drug interaction, a narrow dose window, and a hard purity requirement. Deployed with pharmaceutical-grade product, a low dose, and a clean interaction screen under medical oversight, it is a legitimate frontier bet. Deployed carelessly, it is a genuine hazard.