Comparison
Alpha-GPC vs Methylene Blue
Side-by-side of Alpha-GPC and Methylene Blue. 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.
Alpha-GPC
Alpha GPC supplement profile: 300 to 600 mg dosage, acetylcholine synthesis, attention and reaction-time evidence, side effects, and choline donor comparisons.
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.
Effects at a glance
Alpha-GPC
- •Choline donor supplement, roughly 40% choline by weight; crosses blood-brain barrier efficiently
- •Replicated small gains in attention and reaction time at 300 to 600 mg in healthy adults
- •Standard prescription cognitive medication in much of Europe (Gliatilin) at 1,200 mg/day for vascular cognitive impairment
- •ASCOMALVA trial (n=210) showed cognitive preservation when added to donepezil over 24 months
- •Increases acute power output (~14%, single trial) and transient growth hormone secretion at 600 mg
- •TMAO production raises a contested cardiovascular concern at chronic high doses
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
Side-by-side
| Attribute | Alpha-GPC | Methylene Blue |
|---|---|---|
| Category | supplement | pharmaceutical |
| Also known as | L-Alpha glycerylphosphorylcholine, choline alfoscerate, GPC, alpha-glyceryl phosphorylcholine | Methylthioninium chloride, Provayblue, tetramethylthionine chloride |
| Half-life (hr) ↗ | 4 | 5.5 |
| Typical dose (mg) ↗ | 600 | 70 |
| Dosing frequency | 1 to 3 times daily | 1 to 3 times daily for cognitive use; single IV dose for methemoglobinemia |
| Routes | oral | oral, intravenous |
| Onset (hr) | 1 | 1 |
| Peak (hr) | 2 | 1.5 |
| Molecular weight | 257.22 | 319.85 |
| Molecular formula | C8H20NO6P | C16H18ClN3S |
| Mechanism | Hydrolyzed to free choline and glycerophosphate after absorption; choline supports acetylcholine and phosphatidylcholine synthesis in CNS. | 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. |
| Legal status | Dietary supplement (US); prescription medication in much of Europe | Prescription (injectable, FDA approved); supplement form (oral) widely available; not scheduled |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | Not scheduled in the US |
| Pregnancy | Insufficient data; choline generally recommended in pregnancy | Contraindicated |
| CAS | 28319-77-9 | 61-73-4 |
| PubChem CID | 71920 | 6099 |
| Wikidata | Q411478 | Q409021 |
Safety profile
Alpha-GPC
Common side effects
- mild GI upset
- headache
- dizziness
- occasional insomnia with evening dosing
Contraindications
- established cardiovascular disease (TMAO concern)
- concurrent strong anticholinergic therapy
Interactions
- anticholinergic medications: partial mutual antagonism(minor)
- cholinesterase inhibitors (donepezil): additive cholinergic effect, basis for ASCOMALVA protocol(minor)
- scopolamine: partial counteraction of anticholinergic effect(minor)
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)
Which Should You Take?
Alpha-GPC comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. Methylene Blue is the right call when one of the conditionals below applies.
- → If your priority is athletic performance, pick Alpha-GPC.
- → If your priority is choline supply, pick Alpha-GPC.
- → If your priority is mitochondrial function, pick Methylene Blue.
- → If your priority is antimicrobial action, pick Methylene Blue.
Edge case: If you want to avoid controlled substance, Alpha-GPC is the more accessible choice.
Default choice: Alpha-GPC. Lower friction to source, 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 Alpha-GPC and Methylene Blue?
Alpha-GPC and Methylene Blue differ in category (supplement vs pharmaceutical), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Alpha-GPC or Methylene Blue?
Alpha-GPC half-life is 4 hours; Methylene Blue half-life is 5.5 hours.
Can you stack Alpha-GPC with Methylene Blue?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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