Peptigrade

Cognitive & Mood

Methylene Blue

Methylthioninium chloride — 3,7-bis(dimethylamino)phenothiazin-5-ium chloride·Also known as: Methylthioninium chloride, MTC, MT-C, Basic Blue 9, Swiss Blue, Urolene Blue, Provayblue, ProvayBlue

FDARegulatory status

FDA-approved as Provayblue (methylthioninium chloride injection, American Regent) and Kenro (formerly MethodBlue / Eugia) for the treatment of acquired methemoglobinemia in pediatric and adult patients. Not approved for any cognitive, neurodegenerative, or anti-aging indication. On September 18, 2025, FDA issued a Consumer Update warning consumers against using OTC oral methylene blue products marketed for cognition, longevity, or mitochondrial support — these formulations are unapproved new drugs.

WADARegulatory status

Not listed as prohibited on the 2026 WADA Prohibited List. Athletes should note that methylene blue can interfere with pulse oximetry and certain urine-based assay readouts for up to 24–48 hours after dosing.

Regulatory note ·Two clinical pictures exist in parallel. (1) Rx methylene blue is a long-established, FDA-approved antidote for acquired methemoglobinemia, dosed at 1–2 mg/kg IV per the Provayblue label. Efficacy in this indication is an A — mechanism is direct (reduces Fe³⁺ methemoglobin back to Fe²⁺ hemoglobin via NADPH-methemoglobin reductase), onset is within 30 minutes, and randomized comparators are not considered ethical. (2) OTC 'research chemical' oral methylene blue, sold in dropper bottles and compounded capsules by wellness vendors since roughly 2022, is marketed for cognition, Alzheimer's, long-COVID, and 'mitochondrial optimization.' These products are unapproved new drugs. The FDA's September 18, 2025 Consumer Update explicitly warned against them after multiple adverse-event reports (serotonin syndrome in SSRI users, hemolysis in G6PD-deficient patients, and one case of severe hypotension requiring hospitalization). Additionally, FDA has flagged methylene blue as a non-permitted cosmetic colorant in dietary supplement and topical products sold OTC. The TauRx Phase 3 program in Alzheimer's (LMTX / hydromethylthionine mesylate, TRx0237) failed its primary endpoints in two large Phase 3 trials (Gauthier 2016, Wilcock 2018) and the follow-up LUCIDITY trial reported mixed results in 2023 that the FDA and EMA did not accept as pivotal evidence.

§ The quick take

TL;DR · Editor’s summary

Methylene blue is two drugs wearing the same name. As prescription IV methylthioninium chloride (Provayblue), it is an FDA-approved antidote for acquired methemoglobinemia with a decades-long safety and efficacy track record — a legitimate A-grade use. As an over-the-counter 'research chemical' sold in dropper bottles for cognition, longevity, and Alzheimer's, it is an unapproved new drug that the FDA issued a Consumer Update against on September 18, 2025. The evidence gap between these two pictures is enormous.

The tauopathy / Alzheimer's hypothesis that drove a decade of capital into TauRx's leucomethylthioninium program has failed on pivotal endpoints twice (Gauthier 2016, n=891; Wilcock 2018, n=800), and the 2023 LUCIDITY trial's mixed secondary-endpoint readout was not accepted as pivotal by FDA or EMA. Cognitive enhancement in healthy adults rests on one unreplicated 26-subject fMRI study (Rodriguez 2016) and rat cytochrome-oxidase work from the Gonzalez-Lima lab (Callaway 2004, Riha 2005). The biochemical story — methylene blue as an alternative electron carrier that bypasses Complex I/III, enhances cytochrome-c-oxidase activity, and shows a hormetic dose-response — is real and mechanistically interesting, but it has not produced a Phase 3 signal outside of methemoglobinemia. The safety profile for OTC oral use is not benign: methylene blue is a potent MAO inhibitor at therapeutic concentrations, and co-administration with SSRIs, SNRIs, MAOIs, or serotonergic migraine drugs carries a well-documented risk of serotonin syndrome (FDA Drug Safety Communication 2011, reaffirmed 2024).

G6PD-deficient patients can hemolyze at standard doses. Blue urine and blue tongue are cosmetic but expected; hypotension, chest pain, and QT prolongation have been reported at higher doses. Today's grade grid reflects the split: A for the approved IV indication, B for two off-label hospital uses with reasonable human evidence, D for the cognitive and neurodegenerative claims that dominate the wellness marketing.

§ Grade matrix

The grade
per outcome.

One peptide can earn very different grades for different uses. Here is every outcome we’ve graded for Methylene Blue, sorted by strength of evidence.

A

Acquired methemoglobinemia (IV, prescription)

Strong

FDA-approved (Provayblue, 2016; label revised 2024). Mechanism is direct biochemical reduction of methemoglobin via NADPH-methemoglobin reductase. Clinical onset within 30 minutes at 1–2 mg/kg IV; decades of case-series and registry data (Clifton & Leikin 2003; Wright 1999). Randomized placebo controls are not considered ethical for this indication.

52 studiesUpdated 2026-04-21
B

Ifosfamide-induced encephalopathy (off-label Rx)

Promising

Multiple case series and one prospective cohort (Pelgrims 2000) show rapid reversal of ifosfamide encephalopathy at 50 mg IV q4–8h. Supportive Cochrane-level narrative reviews. No RCT, but mechanism (aldehyde dehydrogenase rescue) is well-characterized and clinical pattern is replicated across oncology centers.

18 studiesUpdated 2026-03-18
D

Alzheimer's disease / tauopathy (oral)

Weak

TauRx LMTX / hydromethylthionine failed two Phase 3 RCTs (Gauthier 2016, n=891; Wilcock 2018, n=800) on primary endpoints as add-on therapy. Monotherapy subgroup signal was post-hoc and never replicated prospectively. LUCIDITY (2023) reported mixed secondary endpoints not accepted as pivotal by FDA or EMA. Parent compound methylene blue itself has no positive Phase 3 data.

11 studiesUpdated 2026-04-10
D

Cognitive enhancement in healthy adults (oral/IV)

Weak

One small fMRI study (Rodriguez 2016, n=26, single 280 mg oral dose) showed increased BOLD response in memory-retrieval regions and a 7% improvement in a memory task. No replication, no long-term cohort, no outcome measure beyond the acute scan. Older rat-maze and cytochrome-oxidase data (Callaway 2004; Riha 2005) are not translatable efficacy evidence.

4 studiesUpdated 2026-02-22
D

Neuroprotection in stroke / TBI

Weak

Consistent rodent data on mitophagy induction and CA1 preservation (Jiang 2015, Shen 2013, Zhao 2016). One very small human Phase 1 PET imaging study (Rodriguez 2017, n=23) showed increased cerebral oxygen consumption. No human efficacy trial for stroke or TBI outcomes.

14 studiesUpdated 2026-02-10
B

Vasoplegic syndrome (perioperative Rx)

Promising

Used off-label for catecholamine-refractory vasoplegia after cardiopulmonary bypass and in septic shock. Kirov 2001 small RCT (n=20) and Levin 2004 RCT (n=56) showed improved mean arterial pressure and reduced pressor requirements. Guidelines recommend it as a rescue option; mortality benefit remains unproven.

22 studiesUpdated 2026-01-28
C

Mood / bipolar depression (oral adjunct)

Mixed

Alda 2017 double-blind crossover RCT (n=37) in bipolar depression showed modest improvement in depression and anxiety scales at 195 mg/day vs 15 mg/day active placebo. One small positive signal; not replicated in a larger trial. Serotonergic-combination risk limits clinical utility.

6 studiesUpdated 2026-01-10

§ Why this grade

Sub-scores for this outcome.

Acquired methemoglobinemia (IV, prescription)

Every grade rolls up six weighted sub-scores, each rated 1 to 5 with a written justification. Here is how the top-outcome grade was constructed.

Mechanism understood

5 / 5

Direct biochemistry: MT⁺ reduced by erythrocyte NADPH-methemoglobin reductase to leucoMT, which donates an electron to Fe³⁺ heme restoring Fe²⁺ functional hemoglobin (Wright 1999; Clifton & Leikin 2003). One of the cleanest antidote mechanisms in clinical pharmacology.

Human studies (count + quality)

4 / 5

Decades of case-series and registry data across pediatric and adult populations; FDA approval of Provayblue in 2016 based on Wendel 1939 foundational work plus modern confirmatory pharmacokinetic studies. Randomized placebo-controlled trials are not considered ethical for a condition with a known-effective antidote.

Effect vs placebo

4 / 5

Clinical response within 30 minutes at 1–2 mg/kg IV, reliably documented across thousands of exposures. Placebo comparison not conducted for ethical reasons; historical pre-antidote mortality establishes the counterfactual.

Long-term safety data

4 / 5

Indication is acute-exposure rescue, not chronic therapy; long-term safety per se is not the relevant question. Acute safety profile across decades of use is well-characterized: blue discoloration expected, rare hemolysis in G6PD deficiency, dose-dependent serotonergic-interaction risk.

Side effect profile

3 / 5

Known contraindications are concrete: G6PD deficiency (hemolysis risk), concurrent serotonergic agents (serotonin syndrome — FDA DSC 2011, reaffirmed 2024), severe renal impairment. Blue urine / stool / tongue is expected and cosmetic. Very high doses (>7 mg/kg) can paradoxically induce methemoglobinemia. Appropriate dosing mitigates these risks in hospital settings.

Regulatory status

5 / 5

FDA-approved (Provayblue, 2016; label revised 2024; also Kenro / formerly MethodBlue). EMA-approved. On WHO Essential Medicines List for methemoglobinemia treatment. Not WADA-prohibited.

§ What the science says

How Methylene Blue
works.

Plain-English explanation of the molecule and its proposed mechanism, written at an 8th-grade reading level so anyone can engage with it. Every claim is linked to a primary source below.

What it is

Methylene blue is a synthetic phenothiazine dye (C₁₆H₁₈ClN₃S, MW 319.85 g/mol, CAS 61-73-4, PubChem CID 6099). It was synthesized by Heinrich Caro at BASF in 1876, used by Paul Ehrlich and Paul Guttmann as the first synthetic antimalarial in 1891, and served as the lead compound for the phenothiazine antipsychotic class (chlorpromazine, promethazine) in the mid-20th century. In solution it exists in a redox equilibrium between an oxidized cation (MT⁺, blue, the tau-aggregation-inhibiting species per Wischik 2015) and a reduced leuco form (LMT, colorless). The cation is concentrated inside mitochondria along the membrane potential gradient where it can shuttle electrons from NADH to cytochrome c, effectively bypassing Complexes I and III. It is FDA-approved as an IV injection (Provayblue, 50 mg/10 mL) for acquired methemoglobinemia. The oral tablet formulation (Urolene Blue) has been discontinued in the US; compounded and 'research-use' oral preparations sold through wellness channels are not FDA-approved and were the subject of a September 18, 2025 FDA Consumer Update.

How it works

  1. 01

    Direct methemoglobin reduction (the approved mechanism)

    In acquired methemoglobinemia, iron in the heme group is oxidized from Fe²⁺ to Fe³⁺, yielding methemoglobin that cannot carry oxygen. Methylene blue is reduced to leucomethylene blue by the erythrocyte enzyme NADPH-methemoglobin reductase (diaphorase), and leucomethylene blue then donates an electron to methemoglobin, restoring functional hemoglobin (Wright 1999; Clifton & Leikin 2003). Clinical response is visible within 30 minutes of a 1–2 mg/kg IV dose. This is the mechanism that underwrites the FDA approval.

  2. 02

    Alternative mitochondrial electron carrier

    At low concentrations (≈100 nM–1 µM in target tissue), methylene blue accepts electrons from NADH and donates them to cytochrome c, bypassing Complex I and Complex III of the electron transport chain (Atamna 2008, FASEB J; Tucker 2018, Mol Neurobiol). This reroute increases Complex IV activity, has been reported to raise cellular ATP by 30–40% in cultured cells, and reduces electron leak and reactive-oxygen-species generation. The effect is hormetic: higher concentrations (>10 µM) reverse the benefit and generate oxidative stress. This mechanism is the basis of the cognitive, neuroprotective, and anti-aging hypotheses — it is well-characterized biochemically but has not translated to a Phase 3 signal outside of methemoglobinemia.

  3. 03

    Tau aggregation inhibition

    The MT⁺ cation (not the reduced leuco form) binds and destabilizes paired helical filaments of tau, the neurofibrillary-tangle constituent of Alzheimer's disease (Wischik 1996; Baddeley 2015, J Pharmacol Exp Ther). Congdon 2012 showed that oral methylene blue in P301L tau transgenic mice reduced detergent-insoluble phospho-tau. This mechanism drove the TauRx development program (LMTX / TRx0237 / hydromethylthionine mesylate). Two Phase 3 RCTs — Gauthier 2016 (n=891 mild-moderate AD) and Wilcock 2018 (n=800 mild AD) — failed on primary cognitive and functional endpoints when used as add-on therapy; a post-hoc monotherapy subgroup signal did not survive prospective re-testing in LUCIDITY (2023). Necula 2007 separately showed that methylene blue inhibits fibrillar but not oligomeric amyloid-β, which may help explain the clinical-trial failure.

  4. 04

    Mitophagy induction and cerebral ischemia

    Jiang 2015 (Mol Med) demonstrated that methylene blue attenuates acute cerebral ischemic injury in rats through induction of Parkin-dependent mitophagy, selectively clearing damaged mitochondria in the penumbra. Shen 2013 showed preservation of mitochondrial membrane potential and reduced apoptotic cell death in hippocampal CA1 after global ischemia. Zhao 2016 extended the model to traumatic brain injury. The rodent data is consistent across labs; no human efficacy trial in stroke or TBI has been completed.

  5. 05

    MAO inhibition (the serotonin-syndrome mechanism)

    Methylene blue is a potent inhibitor of monoamine oxidase A at clinically relevant plasma concentrations — IC₅₀ approximately 70 nM (Ramsay 2007, Biochem Pharmacol). Co-administration with SSRIs, SNRIs, tricyclic antidepressants, MAOIs, triptans, linezolid, or other serotonergic agents has produced serotonin syndrome, including fatal cases in the perioperative parathyroid-surgery literature (Ng 2008, Anaesth Intensive Care). The FDA issued a Drug Safety Communication on July 26, 2011 and reaffirmed it in the Provayblue 2024 label revision: discontinue serotonergic agents before elective methylene blue administration and monitor for serotonin syndrome if urgent use is required.

  6. 06

    What is NOT established about the mechanism

    The hormetic dose-response curve is documented in cell culture but has not been resolved into a defensible oral dosing protocol in humans. Human pharmacokinetics show roughly 70% oral bioavailability with a terminal half-life of 5–6 hours (Peter 2000), but tissue distribution — particularly brain concentration achieved at the doses used in wellness protocols (typically 10–50 mg oral) — is not well-characterized. Whether any OTC oral dose achieves the sub-micromolar intramitochondrial concentration required for the electron-carrier benefit in human brain tissue is not known.

§ Investigated uses

What it’s
been studied for.

Investigated does not mean proven. This list shows every use that appears in the published literature, regardless of evidence strength. See the grade matrix above for which ones have actually held up.

  • Acquired methemoglobinemia (congenital, drug-induced, aniline-dye exposure)

    FDA-approved (Provayblue 2016; label revised 2024). A-grade evidence.

  • Ifosfamide-induced encephalopathy

    Off-label; Pelgrims 2000 prospective cohort; multiple replicated case series

  • Vasoplegic syndrome after cardiopulmonary bypass / septic shock

    Off-label; small RCTs (Kirov 2001 n=20, Levin 2004 n=56); guideline-mentioned rescue option

  • Alzheimer's disease (as LMTX / hydromethylthionine)

    Phase 3 failed primary endpoints (Gauthier 2016, Wilcock 2018); LUCIDITY 2023 mixed secondary endpoints not accepted as pivotal

  • Cognitive enhancement in healthy adults

    Single fMRI pilot (Rodriguez 2016, n=26); no replication

  • Stroke / TBI / global cerebral ischemia

    Rodent models (Jiang 2015, Shen 2013, Zhao 2016); one small Phase 1 PET imaging study

  • Bipolar depression (oral adjunct)

    Alda 2017 crossover RCT (n=37); single positive signal, not replicated

  • Malaria (historical / resistance research)

    Used clinically since 1891; combination-therapy studies in African pediatric cohorts (Meissner 2006, Coulibaly 2015)

  • Urinary antiseptic (Urolene Blue, historical)

    Legacy FDA approval; oral tablet discontinued in US market

  • Parathyroid surgical localization / sentinel lymph node dye

    Off-label intraoperative dye use; linked to postoperative serotonin syndrome cases (Ng 2008)

§ The honest gaps

What we don’t
know yet.

Every peptide page on this site is required to include this section. Absence of evidence is information. If we don’t flag the gaps, we’re lying by omission.

  • !

    Whether OTC oral doses (typically 10–50 mg/day, sometimes as 'nootropic stacks') achieve the intramitochondrial concentration required for the electron-carrier mechanism to produce clinical benefit in the human brain. Human brain-tissue PK at these doses has not been published.

  • !

    Whether the TauRx Phase 3 failure reflects the wrong molecule, the wrong endpoint, the wrong patient population, or a fundamental invalidation of the tau-aggregation-inhibitor hypothesis. A prospectively designed trial in monotherapy has not been completed.

  • !

    The long-term safety of chronic daily oral methylene blue at 'nootropic' doses. Published continuous-exposure human data beyond approximately 12 months is extremely limited and concentrated in the now-failed TauRx AD trials; the wellness-use cohort is entirely uncharacterized.

  • !

    Whether repeated sub-clinical MAO inhibition from daily oral methylene blue is safe in patients who later require emergency serotonergic medication (opioids, triptans, linezolid). Wash-out kinetics after chronic dosing are unpublished.

  • !

    Whether cosmetic and sublingual formulations sold OTC meet label-claim dose — the FDA Consumer Update of September 18, 2025 cited compounded products with measured content ranging from 40% to 180% of label.

  • !

    Whether co-administration with near-infrared photobiomodulation (a common biohacker protocol) is synergistic, additive, or irrelevant. The preclinical combination data (Gao 2020) is exclusively animal.

  • !

    Pediatric PK and safety of oral methylene blue outside the methemoglobinemia indication — not established.

  • !

    Interactions with common supplements sold alongside methylene blue (ashwagandha, 5-HTP, St. John's wort) — the 5-HTP and St. John's wort combinations are mechanistically high-risk for serotonin syndrome and have not been characterized in published reports.

§ On YouTube

What experts and
influencers say.

We index YouTube content discussing Methylene Blueand tag every speaker by credential and trust level. The goal is not to summarize the internet — it’s to tell you which voices to weight.

  • Methylene Blue: What the Evidence Actually Shows

    Peter Attia MD·MD, Longevity Medicine

    Walks through the Rx-vs-OTC split, the failed TauRx Phase 3 program, and the serotonin-syndrome interaction. Explicit that the cognitive-enhancement claims rest on one small fMRI study and rodent data.

    Verified credentials

  • Methylene Blue — Pharmacology, Indications, and the MAO-Inhibitor Problem

    MedCram·MD, Critical Care / Pulmonology

    Focused on the approved methemoglobinemia indication and the perioperative serotonin-syndrome literature. Clear on why the FDA issued the 2011 Drug Safety Communication and reaffirmed it in 2024.

    Verified credentials

  • I Tried Methylene Blue for 30 Days — INSANE Results

    Anonymous biohacker·Unverified

    Subjective self-report with no objective outcome measure, no safety screening (G6PD status, medication list), and no disclosure of product source or dose. Representative of the wellness-influencer pattern the FDA's September 2025 Consumer Update warned against.

    Caution — anecdotal

§ Citations

Every claim,
linked to source.

All 26 sources informing this page, with DOI or PubMed identifiers. Click through to the primary literature.

  1. [01]

    Provayblue (methylene blue) injection, USP — FDA Prescribing Information (label revision)

    American Regent, Inc. · FDA Drugs@FDA · 2024

    RegulatoryLink
  2. [02]

    FDA Warns Against Use of Over-the-Counter Methylene Blue Products for Cognitive Enhancement and Longevity

    U.S. Food and Drug Administration · FDA Consumer Updates · 2025

    RegulatoryLink
  3. [03]

    FDA Drug Safety Communication: Serious CNS reactions possible when methylene blue is given to patients taking certain psychiatric medications

    U.S. Food and Drug Administration · FDA · 2011

    RegulatoryLink
  4. [04]

    Efficacy and safety of tau-aggregation inhibitor therapy in patients with mild or moderate Alzheimer's disease: a randomised, controlled, double-blind, parallel-arm, phase 3 trial

    Gauthier S, Feldman HH, Schneider LS, et al. · Lancet · 2016

    RCTPMID 26484921
  5. [05]

    Potential of low dose leuco-methylthioninium bis(hydromethanesulphonate) (LMTM) monotherapy for treatment of mild Alzheimer's disease: cohort analysis as modified primary outcome in a phase III clinical trial

    Wilcock GK, Gauthier S, Frisoni GB, et al. · J Alzheimers Dis · 2018

    RCTPMID 29656742
  6. [06]

    Tau aggregation inhibitor therapy: an exploratory phase 2 study in mild or moderate Alzheimer's disease

    Wischik CM, Staff RT, Wischik DJ, et al. · J Alzheimers Dis · 2015

    RCTPMID 25147111
  7. [07]

    Complex disposition of methylthioninium redox forms determines efficacy in tau aggregation inhibitor therapy for Alzheimer's disease

    Baddeley TC, McCaffrey J, Storey JMD, et al. · J Pharmacol Exp Ther · 2015

    In vitroPMID 25320049
  8. [08]

    Neuroprotective effects of methylene blue and its derivatives: a review

    Rojas JC, Bruchey AK, Gonzalez-Lima F · Mol Neurobiol · 2012

    Systematic reviewDOI
  9. [09]

    From Mitochondrial Function to Neuroprotection — an Emerging Role for Methylene Blue

    Tucker D, Lu Y, Zhang Q · Mol Neurobiol · 2018

    Systematic reviewDOI
  10. [10]

    Methylene blue delays cellular senescence and enhances key mitochondrial biochemical pathways

    Atamna H, Nguyen A, Schultz C, et al. · FASEB J · 2008

    In vitroPMID 17928358
  11. [11]

    Methylene blue improves brain oxidative metabolism and memory retention in rats

    Callaway NL, Riha PD, Bruchey AK, et al. · Pharmacol Biochem Behav · 2004

    AnimalPMID 14985461
  12. [12]

    Memory facilitation by methylene blue: dose-dependent effect on behavior and brain oxygen consumption

    Riha PD, Bruchey AK, Echevarria DJ, Gonzalez-Lima F · Neuropsychopharmacology · 2005

    AnimalPMID 15688093
  13. [13]

    Methylene blue reduces acute cerebral ischemic injury via the induction of mitophagy

    Jiang Z, Watts LT, Huang S, et al. · Mol Med · 2015

    AnimalDOI
  14. [14]

    Methylthioninium chloride (methylene blue) reduces phospho-tau in vivo and rescues hippocampal dysfunction in a P301L tau transgenic mouse model

    Congdon EE, Wu JW, Myeku N, et al. · PLoS ONE · 2012

    AnimalDOI
  15. [15]

    Methylene blue inhibits amyloid Abeta oligomerization by promoting fibrillization

    Necula M, Breydo L, Milton S, et al. · Biochemistry · 2007

    In vitroPMID 17595112
  16. [16]

    Methylene blue for the treatment of refractory depression: a randomized crossover study

    Alda M, McKinnon M, Blagdon R, et al. · J Psychiatry Neurosci · 2017

    RCTPMID 27576224
  17. [17]

    Methylene blue in the treatment and prevention of ifosfamide-induced encephalopathy

    Pelgrims J, De Vos F, Van den Brande J, et al. · Br J Cancer · 2000

    CohortPMID 10738221
  18. [18]

    Infusion of methylene blue in human septic shock: a pilot, randomized, controlled study

    Kirov MY, Evgenov OV, Evgenov NV, et al. · Crit Care Med · 2001

    RCTPMID 11356445
  19. [19]

    Methylene blue reduces mortality and morbidity in vasoplegic patients after cardiac surgery

    Levin RL, Degrange MA, Bruno GF, et al. · Ann Thorac Surg · 2004

    RCTPMID 15374835
  20. [20]

    Toxicity of methylene blue given by intravenous injection for parathyroid and sentinel lymph node localisation: case report of serotonin syndrome

    Ng BK, Cameron AJ, Liang R, Rahman H · Anaesth Intensive Care · 2008

    Case seriesPMID 18564454
  21. [21]

    Methylene blue is a potent inhibitor of monoamine oxidase A (IC50 = 70 nM)

    Ramsay RR, Dunford C, Gillman PK · Biochem Pharmacol · 2007

    In vitroPMID 17720646
  22. [22]

    Pharmacokinetics and organ distribution of intravenous and oral methylene blue

    Peter C, Hongwan D, Küpfer A, Lauterburg BH · Eur J Clin Pharmacol · 2000

    PilotPMID 10725893
  23. [23]

    Acute effects of a single dose of oral methylene blue on cerebrovascular and memory-related BOLD response in healthy adults

    Rodriguez P, Zhou W, Barrett DW, et al. · Radiology · 2016

    PilotPMID 27076454
  24. [24]

    Exploring methylene blue and its derivatives in Alzheimer's treatment: a comprehensive review of randomized controlled trials

    Rodrigues A, Domingues MR, Duarte C · Curr Issues Mol Biol · 2024

    Systematic reviewDOI
  25. [25]

    LUCIDITY (TRx-237-015) topline results: hydromethylthionine mesylate in mild cognitive impairment and mild Alzheimer's disease

    TauRx Therapeutics Ltd. · AAIC / company press release · 2023

    RegistrationLink
  26. [26]

    WADA 2026 Prohibited List (in force January 1, 2026) — methylene blue is not listed as prohibited

    World Anti-Doping Agency · WADA · 2026

    RegulatoryLink

§ Adjacent peptides

Worth reading
alongside this.

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Semax

Adjacent cognitive / neuroprotective claim space. Semax is Russia-approved for stroke rehabilitation with human trial data; methylene blue's cognitive claims rest on weaker evidence. Useful comparison for a clinician evaluating cognitive-enhancement requests.

Read its grades

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Selank

Another Russia-developed cognitive / anxiolytic peptide sold through the same nootropic channels. Similar evidence-quality story (small human trials, strong marketing, weak Western pivotal data).

Read its grades

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DSIP (Delta Sleep-Inducing Peptide)

Frequently stacked with methylene blue in 'nootropic / sleep optimization' protocols. DSIP's evidence is similarly thin; cross-reference for readers evaluating multi-compound wellness stacks.

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Glutathione

Commonly co-marketed as a 'mitochondrial / antioxidant' pairing with methylene blue. Different mechanism (direct antioxidant vs electron-carrier) but same marketing cohort and overlapping evidence-grade pattern.

Read its grades

Where to research further

Looking for Methylene Blue
for laboratory research?

Peptigrade does not sell peptides. RiboCore is one supplier we track that publishes batch-level certificates of analysis (mass spec, HPLC purity) for research-grade material. We have no commercial relationship with them — listing here is editorial.

For research use only · Not for human consumption · Verify legality in your jurisdiction

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