Methylene blue Reference

Plain English

What it is

Methylene blue is a deep-blue dye that is also an FDA-approved prescription medicine. As a drug it is cleared to treat a blood disorder called methemoglobinemia, where the blood cannot carry oxygen normally. It is not a controlled substance.

What people use it for

Apart from that approved use, some people take small amounts off-label, meaning for an unapproved purpose, hoping to sharpen focus, memory, and energy or to support the tiny energy factories inside cells (mitochondria). These brain and energy uses are not what the drug was approved for.

What the science shows

The evidence behind those cognitive claims is weak. It rests mostly on lab and animal work plus a few small early human studies, and large trials have not shown a clear benefit for memory or dementia.

The catch

Methylene blue blocks an enzyme that clears serotonin, a brain chemical, so it acts like a strong monoamine oxidase (MAO) inhibitor. Combining it with antidepressants or other serotonin-raising drugs, such as SSRIs, SNRIs, MAOIs, or tramadol, can set off serotonin syndrome, a dangerous and sometimes fatal reaction that the FDA warns about. It is a prescription drug, not a casual supplement.

Reference summary

Methylene blue is label-verified for methemoglobinemia. Low-dose nootropic literature is preclinical and small human pilot trials.

Regulatory and posture

Categories

Nootropic, Metabolic

Aliases

Provayblue, Methylthioninium chloride, Methylene blue USP

Evidence posture

human - FDA-approved at therapeutic doses for methemoglobinemia. Low-dose nootropic / cognitive use is off-label. Concomitant SSRIs / MAOIs / serotonergic agents can produce serotonin syndrome - methylene blue is a potent MAO-A inhibitor at therapeutic doses.

Regulatory status

FDA-approved prescription medication (Provayblue) for acquired methemoglobinemia. Low-dose nootropic / cognitive use is off-label. Not a controlled substance.

Content review status

label verified