Comparison
Methylene Blue vs Vitamin D3 + K2
Side-by-side of Methylene Blue and Vitamin D3 + K2. 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.
Methylene Blue
Methylene blue as a nootropic: low-dose cognitive enhancement, mitochondrial electron cycling, brain oxygen uptake, SSRI interaction risk, typical 0.5 to 4 mg.
Vitamin D3 + K2
Vitamin D3 K2 supplement profile: cholecalciferol at 1000-4000 IU/day corrects deficiency, MK-7 directs calcium to bone, away from arteries.
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
Vitamin D3 + K2
- •Reduces non-vertebral fractures 10-20% in older adults at 800 IU/day or above when combined with calcium
- •VITAL trial showed neutral results on primary CV and cancer endpoints at 2000 IU/day over 5 years
- •Vitamin D supplementation reduces respiratory infection incidence ~10-20% in deficient populations
- •K2 MK-7 has 72-hour plasma half-life vs 1-2 hours for MK-4; once-daily dosing is sufficient
- •Synergy hypothesis is largely preclinical; dedicated combination RCTs are limited
- •Daily dosing outperforms bolus dosing for immune and infection outcomes
Side-by-side
| Attribute | Methylene Blue | Vitamin D3 + K2 |
|---|---|---|
| Category | pharmaceutical | supplement |
| Also known as | Methylthioninium chloride, Provayblue, tetramethylthionine chloride | cholecalciferol + menaquinone, D3/K2, vitamin D3 with MK-7 |
| Half-life (hr) ↗ | 5.5 | 360 |
| Typical dose (mg) ↗ | 70 | 0.05 |
| Dosing frequency | 1 to 3 times daily for cognitive use; single IV dose for methemoglobinemia | daily with a fat-containing meal |
| Routes | oral, intravenous | oral |
| Onset (hr) | 1 | 24 |
| Peak (hr) | 1.5 | 168 |
| Molecular weight | 319.85 | 384.64 |
| Molecular formula | C16H18ClN3S | C27H44O (D3); C46H64O2 (MK-7) |
| 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. | D3 converts to calcidiol then calcitriol, activating the vitamin D receptor (VDR) to increase intestinal calcium absorption and modulate immune and bone gene transcription. K2 carboxylates osteocalcin and matrix Gla protein, directing calcium toward bone and inhibiting vascular calcification. |
| Legal status | Prescription (injectable, FDA approved); supplement form (oral) widely available; not scheduled | Dietary supplement (global) |
| WADA status | allowed | allowed |
| DEA / Rx | Not scheduled in the US | Not scheduled |
| Pregnancy | Contraindicated | Recommended at standard doses for fetal bone development; consult clinician at higher doses |
| CAS | 61-73-4 | 67-97-0 |
| PubChem CID | 6099 | 5280795 |
| Wikidata | Q409021 | Q139347 |
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)
Vitamin D3 + K2
Common side effects
- GI upset at high doses
- headache (rare)
- hypercalcemia (only at sustained very high D3 doses)
Contraindications
- hypercalcemia
- sarcoidosis
- active hyperparathyroidism
- warfarin therapy (K2 component requires stable intake)
Interactions
- warfarin: K2 component can affect anticoagulation; maintain stable intake and inform anticoagulation clinic(moderate)
- thiazide diuretics: additive calcium retention; hypercalcemia risk with high-dose D3(moderate)
- digoxin and calcium channel blockers: additive effects from D3-induced hypercalcemia(moderate)
- glucocorticoids: reduced vitamin D efficacy and bone effects(moderate)
- cholestyramine and orlistat: bind fat-soluble vitamins; separate dosing by 2 to 4 hours(moderate)
Which Should You Take?
Vitamin D3 + K2 comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Methylene Blue is the right call when one of the conditionals below applies.
- → If your priority is focus or working memory, pick Methylene Blue.
- → If your priority is mitochondrial function, pick Methylene Blue.
- → If your priority is bone density, pick Vitamin D3 + K2.
- → If your priority is healthspan extension, pick Vitamin D3 + K2.
Edge case: If you want to avoid controlled substance, Vitamin D3 + K2 is the more accessible choice.
Default choice: Vitamin D3 + K2. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Methylene Blue only if your priority sits squarely in the goals it owns 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 Vitamin D3 + K2?
Methylene Blue and Vitamin D3 + K2 differ in category (pharmaceutical vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Methylene Blue or Vitamin D3 + K2?
Methylene Blue half-life is 5.5 hours; Vitamin D3 + K2 half-life is 360 hours.
Can you stack Methylene Blue with Vitamin D3 + K2?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper