Skip to content
BiologicalX

Comparison

Methylene Blue vs Modafinil

Side-by-side of Methylene Blue and Modafinil. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.

Effects at a glance

Methylene Blue

  • FDA approved for methemoglobinemia and ifosfamide-induced encephalopathy
  • Mitochondrial electron-transport support at low doses (0.5 to 4 mg/kg) via cytochrome c shuttle
  • Potent MAO-A inhibitor; serotonin syndrome risk with SSRIs, SNRIs, MAOIs, fentanyl, tramadol, St John's wort
  • Causes harmless blue-green urine and sweat coloration; useful adherence marker
  • G6PD deficiency is an absolute contraindication; can trigger massive hemolysis
  • Cognitive-enhancement evidence is preliminary, mostly preclinical and small fMRI trials

Modafinil

  • FDA approved in 1998 for narcolepsy, with later additions for shift-work sleep disorder and OSA residual sleepiness
  • Schedule IV controlled substance in the US; prescription-only in EU, UK, Australia
  • Increases wakefulness via weak dopamine reuptake inhibition plus histaminergic, noradrenergic, and orexinergic activation
  • Long half-life of 12 to 15 hours requires morning dosing to avoid sleep disruption
  • Modest cognitive enhancement signal in non-sleep-deprived adults at 100 to 200 mg (Battleday meta-review 2015)
  • Substantial CYP3A4 induction reduces hormonal contraceptive efficacy; barrier methods recommended

Side-by-side

Attribute Methylene Blue Modafinil
Category pharmaceutical pharmaceutical
Also known as Methylthioninium chloride, Provayblue, tetramethylthionine chloride Provigil, Modalert, Modvigil, diphenylmethylsulfinyl-acetamide
Half-life (hr) 5.5 13
Typical dose (mg) 70 200
Dosing frequency 1 to 3 times daily for cognitive use; single IV dose for methemoglobinemia daily, morning
Routes oral, intravenous oral
Onset (hr) 1 1
Peak (hr) 1.5 3
Molecular weight 319.85 273.35
Molecular formula C16H18ClN3S C15H15NO2S
Mechanism Mitochondrial electron carrier at low doses (cytochrome c shuttle to complex IV) and methemoglobin reductase substrate at higher doses; potent MAO-A inhibitor across the dose range. Weak dopamine reuptake inhibition plus downstream activation of histaminergic, noradrenergic, and orexinergic wake-promoting systems.
Legal status Prescription (injectable, FDA approved); supplement form (oral) widely available; not scheduled Schedule IV (US); prescription-only globally; not a supplement
WADA status allowed banned
DEA / Rx Not scheduled in the US Schedule IV
Pregnancy Contraindicated Not recommended
CAS 61-73-4 68693-11-8
PubChem CID 6099 4236
Wikidata Q409021 Q422968

Safety profile

Methylene Blue

Common side effects

  • blue-green urine and sweat
  • skin and oral mucosa staining
  • GI upset
  • headache
  • dizziness

Contraindications

  • G6PD deficiency
  • pregnancy
  • concurrent serotonergic medication
  • severe renal impairment
  • infants under 6 months

Interactions

  • SSRIs and SNRIs: serotonin syndrome, potentially fatal(major)
  • MAOIs: additive MAO inhibition, serotonin syndrome risk(major)
  • fentanyl, tramadol, meperidine: serotonin syndrome risk(major)
  • dextromethorphan: serotonin syndrome risk(major)
  • St John's wort: serotonin syndrome risk(major)
  • lithium: additive serotonergic risk(major)

Modafinil

Common side effects

  • headache
  • nausea
  • anxiety
  • insomnia (with late-day dosing)
  • dry mouth
  • mild blood pressure elevation

Contraindications

  • recent myocardial infarction
  • unstable angina
  • left ventricular hypertrophy
  • significant arrhythmia
  • history of Stevens-Johnson syndrome
  • psychotic disorders
  • pregnancy
  • concurrent MAOI use

Interactions

  • hormonal contraceptives: CYP3A4 induction reduces contraceptive efficacy; use barrier method(major)
  • cyclosporine: reduced cyclosporine levels via CYP3A4 induction(major)
  • warfarin: CYP2C9 inhibition raises INR(moderate)
  • phenytoin: CYP2C19 inhibition raises phenytoin levels(moderate)
  • MAOIs: potential hypertensive reaction(major)
  • classical stimulants (amphetamine, methylphenidate): additive cardiovascular and sleep-disruption effects(moderate)

Which Should You Take?

Methylene Blue and Modafinil score evenly on the criteria we weight (goal breadth, legal accessibility, evidence depth). The conditionals below should drive the decision more than any aggregate score.

  • If your priority is mitochondrial function, pick Methylene Blue.
  • If your priority is antimicrobial action, pick Methylene Blue.
  • If your priority is wakefulness, pick Modafinil.
  • If your priority is fatigue resistance, pick Modafinil.

Edge case: Methylene Blue is contraindicated in pregnancy; Modafinil is the safer pick if that applies.

Default choice: either is defensible. Methylene Blue edges out on goal breadth + legal accessibility; Modafinil is the right call if your priority sits in the goals listed above.

This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.

Common questions

What is the difference between Methylene Blue and Modafinil?

Methylene Blue and Modafinil differ in category (pharmaceutical vs pharmaceutical), mechanism, and typical dosing. See the side-by-side table for full details.

Which has a longer half-life, Methylene Blue or Modafinil?

Methylene Blue half-life is 5.5 hours; Modafinil half-life is 13 hours.

Can you stack Methylene Blue with Modafinil?

Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.

Go deeper