Reviewed by Dr. Jason Wright, D.O. · September 23, 2026
The science
How it works
Backup electron carrier
In the mitochondria, it can shuttle electrons along the energy chain, helping cells make ATP when that chain is under strain.
Antioxidant at low doses
At low doses it reduces oxidative stress. At high doses it can do the opposite, which is why dosing stays low.
Blocks MAO-A
It inhibits the enzyme that breaks down serotonin. That is the source of its most important drug interaction.
Old drug, new use
Used in medicine for more than a century, most notably as the IV treatment for methemoglobinemia.
It is FDA-approved only as an IV treatment for methemoglobinemia. Evidence for low-dose oral use for memory and energy comes from small studies.
Dosing
Your dosing plan
Dr. Wright sets your exact dose within this range at your visit.
Starting dose
FormOral capsule
Dose5 mg
ScheduleOnce daily in the morning
Based onPharmacy labeling, clinical practice
If tolerated
FormOral capsule
Dose10–25 mg
ScheduleOnce daily in the morning, stepped up slowly
Based onClinical practice
Before starting
Form—
DoseFull medication review and G6PD blood test
ScheduleRequired for every patient
Based onSafety screening
Side effects
Side effects and what to expect
Blue or green urineVery common · From the first dose
Harmless and expected.
Blue-tinged tongue or stoolCommon · After doses
Harmless.
Nausea or stomach upsetUncommon · First week
Take it with water. Let us know if it persists.
HeadacheUncommon · First week
Usually passes.
Serotonin syndromeRare · With serotonergic drugs
This is why we screen every medication before prescribing.
A note from Dr. Wright
Methylene blue is one of medicine’s oldest drugs. At low doses it helps cells produce energy more efficiently, which is why people use it for mental clarity and steady energy. It also interacts with some of the most common medications in America, so I only prescribe it after going through your full medication list, and I start low.
Dr. Jason Wright, D.O. · Board certified, American Board of Cosmetic Surgery
Cost & access
Getting started with Methylene Blue
Methylene Blue
30 capsules · 5, 10, 15, or 25 mg · one each morning · Labeled in your name
Anyone taking an SSRI, SNRI, MAOI, tricyclic antidepressant, lithium, tramadol, dextromethorphan, St. John’s Wort, or another serotonergic drug; anyone with G6PD deficiency; and anyone pregnant or breastfeeding. These are firm exclusions.
Why the G6PD test?
People with G6PD deficiency can develop hemolysis, a breakdown of red blood cells, from methylene blue. A simple blood test rules it out.
What about the antidepressant interaction?
The FDA has warned about serotonin syndrome when methylene blue is given with serotonergic antidepressants. The reported cases involved IV doses during surgery, and the risk at low oral doses isn’t known, so we treat it as a hard stop.
Will it turn my urine blue?
Yes, blue or green. That is expected and harmless.
What does the research show?
A small imaging study found a single dose improved memory recall and related brain activity. Larger trials of a related compound for Alzheimer’s disease did not show benefit.
Research
Supporting studies
FDA safety communication: methylene blue and serotonergic psychiatric medications
