supplementPrescription only (US)Methylene blue (ProvayBlue) is FDA-approved for methemoglobinemia, not for cognition or longevityIt is a monoamine oxidase inhibitor and can cause serotonin syndrome with serotonergic drugsContraindicated in G6PD deficiency
Methylene BlueBenefits, Dosage & Interactions
Also known as: MB
Methylene Blue (MB) is a synthetic organic compound that belongs to the phenothiazine class. It is perhaps best known for its historical use as a dye for staining tissues and bacteria, and as a treatment for methemoglobinemia. Research on Methylene Blue focuses on cognition and mood and mitochondrial function.
How much Methylene Blue do people take?
The brain-imaging trial used a single oral dose of roughly 0.5-4 mg/kg; the septic-shock trial infused 100 mg intravenously. Route reported: Oral in the cognition trial, intravenous in the critical-care trial. Frequency reported: Single dose in the imaging trial; three daily infusions in the septic-shock trial. These are amounts documented in the cited studies and labels for Methylene Blue — they are reported for reference, not a recommendation. Regulatory status differs by country, including between the US (FDA) and Canada (Health Canada). Confirm any amount with a licensed clinician before you take it.
See the full reported protocol and its sourcesResearched by DoseRoutine Research TeamReviewed for accuracy by Nicholas Alexander, RSE, SO, PMPLast updated Educational reference only — not medical advice. Always confirm dosing and safety decisions with a licensed clinician.
Evidence: Strong — 2 human randomized trials and regulatory approval on file.
Evidence strengthStrong · 4/4
PreclinicalStrong human evidence
2 human randomized trials and regulatory approval on file.
Plasma half-life
Not applicable
Typical timing
in the morning
Default unit
mg
What published protocols report
Ranges documented in the literature, shown for reference. DoseRoutine does not recommend an amount — your prescriber or the product label sets the dose.
Reported for Methylene Blue in the cited sources. Published ranges are not dosing advice.
References & evidence
Documents the Methylene Blue entry is written from. Each number matches an inline marker above.
- [1]Multimodal Randomized Functional MR Imaging of the Effects of Methylene Blue in the Human BrainRodriguez P, Zhou W, Barrett DW, et al. · Radiology · 2016 · Peer-reviewed · PMID 27351678
- [2]Early adjunctive methylene blue in patients with septic shock: a randomized controlled trialIbarra-Estrada M, Kattan E, Aguilera-Gonzalez P, et al. · Critical Care · 2023 · Peer-reviewed · PMID 36915146
- [3]The Potentials of Methylene Blue as an Anti-Aging DrugXue H, Thaivalappil A, Cao K · Cells · 2021 · Peer-reviewed · PMID 34943887
References & Evidence
Sources on this page that document Methylene Blue dosing, timing and safety.
- [1]National Center for Biotechnology Information View source
Educational information only — not medical advice. Dose ranges vary by person, indication and prescriber.
What is Methylene Blue studied for?
What is Methylene Blue?Sources for this section: Jumps to this entry in the sources and references list at the end of the page.
Methylene Blue (MB) is a synthetic organic compound that belongs to the phenothiazine class. It is perhaps best known for its historical use as a dye for staining tissues and bacteria, and as a treatment for methemoglobinemia. However, in recent decades, research has expanded its potential applications, particularly in the fields of neuroscience and mitochondrial health. It is characterized by its deep blue color in solution.
MB has a wide range of biological activities, acting as an electron carrier within the mitochondria, an antioxidant, and a modulator of various signaling pathways. It has been investigated for its potential neuroprotective effects, cognitive enhancement, and anti-aging properties. While Methylene Blue is available as a supplement, it is also used as a prescription medication for specific medical conditions. It is important to distinguish between these uses and to understand that the information provided here pertains to its general properties and research, and not to specific medical treatments.
What does the research say about Methylene Blue?
Tap a section to expand.
Methylene Blue's primary mechanism of action involves its interaction with mitochondrial electron transport chain (ETC). It acts as an alternative electron acceptor and donor, effectively bypassing dysfunctional complexes within the ETC, particularly Complex I and Complex III. This action is thought to enhance mitochondrial respiration and ATP production, especially in conditions where mitochondrial function is impaired. By facilitating electron flow, MB can improve cellular energy metabolism.
Beyond its role in the ETC, Methylene Blue also demonstrates antioxidant properties. It can scavenge reactive oxygen species (ROS) and reduce oxidative stress, which is a key contributor to cellular damage and aging. It has been shown to activate the Nrf2 pathway, a master regulator of antioxidant and detoxification genes. (Source: PubChem)
Furthermore, MB has been observed to inhibit monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B) enzymes, which are involved in the breakdown of neurotransmitters like serotonin, norepinephrine, and dopamine. This inhibition could contribute to its potential cognitive and mood-modulating effects. It also interacts with nitric oxide (NO) signaling, potentially by inhibiting soluble guanylate cyclase, leading to complex effects on vascular tone and neuronal signaling. (Source: DrugBank)
Source for this section: Sources for How does Methylene Blue work?: Jumps to this entry in the sources and references list at the end of the page.
Research into Methylene Blue suggests several potential benefits, primarily centered around brain health, mitochondrial function, and processes related to longevity:
* **Cognitive Enhancement:** Studies have explored MB's potential to improve memory and cognitive function, particularly in animal models and some human studies. Its ability to enhance mitochondrial efficiency and neuroprotection is believed to underlie these effects. (Source: PubChem)
* **Neuroprotection:** Methylene Blue has been investigated for its neuroprotective properties in various neurological conditions, including stroke, Parkinson's disease, and Alzheimer's disease models. It is thought to protect neurons from oxidative stress and mitochondrial dysfunction. (Source: PubChem)
* **Mitochondrial Support:** By acting as an electron donor/acceptor in the electron transport chain, MB can improve mitochondrial respiration and ATP production, which is crucial for cellular energy and function. This is particularly relevant for tissues with high energy demands, such as the brain and heart. (Source: DrugBank)
* **Antioxidant Activity:** Methylene Blue exhibits antioxidant effects by scavenging reactive oxygen species and upregulating endogenous antioxidant defenses, helping to mitigate cellular damage. (Source: PubChem)
* **Longevity Research:** Due to its mitochondrial and antioxidant effects, MB has gained interest in the field of longevity and anti-aging research, with studies exploring its potential to extend lifespan in various organisms. (Source: PubChem)
It is important to note that while research is promising, many of these benefits are still under investigation, and more robust human clinical trials are needed to fully establish efficacy for these applications.
The evidence supporting the various uses of Methylene Blue comes from a combination of in vitro studies, animal models, and some human clinical trials. Its established medical uses, such as for methemoglobinemia, are supported by a long history of clinical application and FDA approval (Source: FDA label). For its 'off-label' or investigational uses related to brain health, mitochondrial function, and longevity, the evidence is primarily derived from:
* **Preclinical Studies:** Numerous studies in cell cultures and animal models (e.g., rodents, C. elegans, Drosophila) have demonstrated the neuroprotective, cognitive enhancing, and mitochondrial-boosting effects of Methylene Blue. These studies provide strong mechanistic insights and rationale for further human investigation. (Source: PubChem)
* **Early Human Trials:** Some small-scale human trials have explored MB's effects on memory, mood, and brain activity. While these studies have shown some promising results, such as improved memory in healthy individuals or beneficial effects in certain neurological conditions, they are often limited by sample size, duration, and the need for replication in larger, more diverse populations. (Source: PubMed, various research articles).
While the scientific interest in MB's broader applications is high, much of the evidence for its use as a 'supplement' for cognitive enhancement or longevity is still considered emerging or preliminary from a robust clinical perspective. It's crucial to differentiate between its approved medical uses and its investigational or supplemental applications.
Methylene Blue can cause a range of side effects, which may vary depending on the dose and individual sensitivity:
* **Common Side Effects:** The most common and noticeable side effect is the blue or blue-green discoloration of urine, feces, and occasionally skin. This is usually harmless but can be startling. Other common side effects include nausea, vomiting, abdominal discomfort, diarrhea, and dizziness.
* **Gastrointestinal Issues:** Users may experience digestive upset.
* **Headache:** Headaches have been reported.
* **Hypertension (High Blood Pressure):** Methylene Blue can increase blood pressure in some individuals.
* **Serotonin Syndrome Risk:** When combined with certain other compounds (see 'Do Not Mix'), Methylene Blue can increase serotonin levels, leading to a risk of serotonin syndrome, which can be life-threatening.
* **Hemolytic Anemia:** In individuals with G6PD deficiency, Methylene Blue can cause hemolytic anemia, a serious condition where red blood cells are destroyed.
* **Cardiac Effects:** Rare but serious cardiac effects, such as arrhythmias, have been reported at higher doses or in susceptible individuals.
* **Skin/Mucous Membrane Discoloration:** Beyond urine, prolonged or high-dose use can lead to a bluish tint to the skin or mucous membranes.
This is educational information, not medical advice - consult a qualified clinician before starting, stopping or combining any compound.
Several warnings are associated with the use of Methylene Blue:
* **G6PD Deficiency:** Methylene Blue should not be used in individuals with Glucose-6-phosphate dehydrogenase (G6PD) deficiency, as it can cause severe and potentially fatal hemolytic anemia. Screening for G6PD deficiency is recommended before use if there is any suspicion.
* **Renal Impairment:** Use with caution in individuals with severe kidney impairment, as MB is primarily excreted by the kidneys and accumulation could occur.
* **Hepatic Impairment:** Caution is advised in individuals with severe liver impairment, as liver metabolism can affect MB's clearance.
* **Pregnancy and Breastfeeding:** Methylene Blue is generally not recommended during pregnancy or breastfeeding due to insufficient safety data. Consult a healthcare professional.
* **Medical Supervision:** Due to its potent biological activity and potential for serious side effects and interactions, Methylene Blue should ideally be used under the supervision of a licensed healthcare professional, especially for therapeutic purposes or if you have underlying health conditions.
* **Driving/Operating Machinery:** Methylene Blue can cause dizziness or confusion in some individuals. Caution is advised when driving or operating heavy machinery until you know how you react to it.
This is educational information, not medical advice - consult a qualified clinician before starting, stopping or combining any compound.
Methylene Blue is strictly contraindicated in several situations:
* **G6PD Deficiency:** As mentioned in 'Warnings', this is a critical contraindication due to the risk of severe hemolytic anemia.
* **Known Hypersensitivity:** Individuals with a known allergy or hypersensitivity to Methylene Blue or any phenothiazine derivatives should not use it.
* **Severe Renal Failure:** In cases of severe kidney failure, Methylene Blue is contraindicated due to increased risk of accumulation and toxicity.
* **Concomitant Serotonergic Drugs:** Due to the risk of serotonin syndrome, Methylene Blue is contraindicated with serotonergic drugs such as SSRIs, SNRIs, MAOIs, tricyclic antidepressants, and certain opioids (see 'Do Not Mix' for more details).
* **Pregnancy (Category X):** While some sources list it differently, Methylene Blue is often considered contraindicated in pregnancy due to potential fetal harm, though comprehensive human data is limited. (Source: EMA SmPC for medical uses sometimes lists this)
* **History of Methemoglobinemia Due to Chlorate Poisoning:** Methylene Blue is contraindicated in this specific type of methemoglobinemia, ironically, because it can exacerbate the condition rather than treat it.
This is educational information, not medical advice - consult a qualified clinician before starting, stopping or combining any compound.
Methylene Blue has significant interactions with several classes of drugs and should not be mixed without strict medical supervision:
* **Serotonergic Drugs (SSRIs, SNRIs, MAOIs, Tricyclic Antidepressants, etc.):** This is the most critical interaction. Methylene Blue is a potent reversible inhibitor of monoamine oxidase (MAO), particularly MAO-A. Concomitant use with other serotonergic agents can lead to a dangerous and potentially fatal condition known as **Serotonin Syndrome**. Symptoms include mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination), and gastrointestinal symptoms. If you are taking any medication that affects serotonin levels, Methylene Blue should be avoided entirely or used with extreme caution and under strict medical guidance after a washout period.
* **Other MAOIs:** Combining Methylene Blue with other monoamine oxidase inhibitors (e.g., phenelzine, selegiline, tranylcypromine) can dangerously potentiate their effects, leading to hypertensive crises or severe serotonin syndrome.
* **Sympathomimetics:** Drugs that stimulate the sympathetic nervous system (e.g., ephedrine, pseudoephedrine, amphetamines, dopamine, norepinephrine) may have enhanced effects when combined with MB due to MAO inhibition, leading to increased blood pressure and heart rate.
* **Opioids (e.g., Fentanyl, Tramadol):** Some opioids have serotonergic activity. Combining them with Methylene Blue increases the risk of serotonin syndrome.
* **Certain Antimalarial Drugs:** Co-administration with some antimalarials, especially primaquine, can increase the risk of hemolytic anemia in G6PD deficient individuals.
* **Warfarin and other Anticoagulants:** Methylene Blue may potentially affect coagulation, though evidence is less robust than for serotonergic interactions. Caution is advised.
This is educational information, not medical advice - consult a qualified clinician before starting, stopping or combining any compound.
For supplemental use, Methylene Blue is typically taken in the morning. This timing is often chosen due to its potential stimulating and cognitive-enhancing effects, which might interfere with sleep if taken later in the day. It can be taken either with or without food, as its absorption is not typically food-dependent. However, taking it with food might help reduce potential gastrointestinal upset for some individuals. The specific dose and administration schedule for Methylene Blue, especially for therapeutic indications, must be directed by a licensed clinician.
Source for this section: Sources for When should you take Methylene Blue?: Jumps to this entry in the sources and references list at the end of the page.
Put it into practice
Reading about Methylene Blue is the first step — DoseRoutine helps you act on it. These free tools turn what you just learned into a routine.
What interacts with Methylene Blue?
| Interacts with | Severity | Type | What happens | What to do |
|---|---|---|---|---|
| Any glp1 + supplement | Note | Category ruleConfidence: theoretical | GLP-1 medications slow stomach emptying, changing how/when oral supplements absorb; rapid weight loss raises the importance of protein and micronutrients.Source pending | Time oral supplements when nausea is lowest; prioritize protein and micronutrients; discuss with your provider. |
| Any supplement + medication | Note | Category ruleConfidence: theoretical | Some supplements change how the body processes medications (absorption, liver enzymes, or additive effects).Source pending | Specific pairs are checked against a licensed drug database and shown with their own severity. Always confirm with your provider or pharmacist. |
Frequently asked questions about Methylene Blue
In medicine, Methylene Blue is primarily used to treat methemoglobinemia, a blood disorder where oxygen transport is impaired. It also has uses as a diagnostic stain, an antiseptic, and sometimes for cyanide poisoning or as a virucide in blood transfusions.
Yes, one of the most common and noticeable effects of Methylene Blue is that it turns urine blue or blue-green. It can also discolor feces and, in some cases, may cause a temporary bluish tint to the skin or mucous membranes.
No, Methylene Blue is not safe for everyone. It is strongly contraindicated in individuals with Glucose-6-phosphate dehydrogenase (G6PD) deficiency, as it can cause life-threatening hemolytic anemia. It also has significant interactions with many common medications, particularly antidepressants and other serotonergic drugs, and should be avoided in such cases due to the risk of serotonin syndrome.
Methylene Blue has an average half-life of about 14 hours. This means it takes approximately 14 hours for half of the compound to be eliminated from the body. Complete elimination typically takes several half-lives.
Absolutely not. Methylene Blue should never be taken with antidepressants (SSRIs, SNRIs, MAOIs, etc.) or any other serotonergic drugs due to the high risk of developing serotonin syndrome, which can be a severe and life-threatening condition. Always consult your clinician before combining any supplements with prescription medications.
Methylene Blue is a supplement, and interactions are possible with prescriptions, hormones, peptides and other supplements in the same routine. Because Methylene Blue is usually taken in the morning, most avoidable conflicts come from what else lands in that same window. Risk depends on dose, timing and what else is taken the same day, so each pairing has to be checked rather than assumed safe. The free checker at https://doseroutine.com/interaction-checker covers Methylene Blue with no sign-up.
Methylene Blue is typically taken in the morning. Ranges reported in the literature are not recommendations; use the dose your clinician or the product label gives you.
Combining a supplement like Methylene Blue with TRT is usually a question of labs rather than a blanket yes or no: the ester, injection interval and any aromatase inhibitor all change the answer. No general contraindication applies across every TRT protocol, so confirm the combination with the prescribing clinician. See the free TRT interaction reference: https://doseroutine.com/trt-supplement-interactions
Each peptide class carries its own profile against Methylene Blue: a healing peptide raises different questions than a GLP-1 agonist or a growth-hormone secretagogue. Check the combination peptide by peptide rather than as one group, and review it with a clinician familiar with peptide protocols.
Published frequency for Methylene Blue varies by protocol and formulation, so the label or prescription is what sets it. It is typically taken in the morning. Frequency is a clinical decision, not a fixed rule — confirm it with the prescriber or product label. Comparison of apps that keep a schedule like this: https://doseroutine.com/best-dose-tracking-apps
The effect of a missed dose of Methylene Blue depends on the protocol and formulation you are on. Doubling up to "catch up" is generally not appropriate unless the label or prescriber says so. Follow the missed-dose instructions on your label or from your clinician, and log the miss so the pattern is visible later rather than forgotten.
For Methylene Blue the useful record is the dose, the time it was actually taken, and what else was taken in the same window. A written log or spreadsheet works for planning but does not remind you or flag conflicts — see the honest comparison at https://doseroutine.com/vs/spreadsheet and the wider roundup at https://doseroutine.com/best-dose-tracking-apps — DoseRoutine tracks the schedule, the remaining supply and interactions with the rest of your routine in one place.
The brain-imaging trial used a single oral dose of roughly 0.5-4 mg/kg; the septic-shock trial infused 100 mg intravenously. Route reported: Oral in the cognition trial, intravenous in the critical-care trial. Frequency reported: Single dose in the imaging trial; three daily infusions in the septic-shock trial. These are amounts documented in the cited studies and labels for Methylene Blue — they are reported for reference, not a recommendation. Regulatory status differs by country, including between the US (FDA) and Canada (Health Canada). Confirm any amount with a licensed clinician before you take it.
Which studies looked at Methylene Blue?
Peer-reviewed research indexed in PubMed. Each entry links to the original record.
- 1.Early adjunctive methylene blue in patients with septic shock: a randomized controlled trial(opens PubMed in a new tab)Crit Care · 2023 · PMID 36915146 · https://pubmed.ncbi.nlm.nih.gov/36915146/
- 2.The Potentials of Methylene Blue as an Anti-Aging Drug(opens PubMed in a new tab)Cells · 2021 · PMID 34943887 · https://pubmed.ncbi.nlm.nih.gov/34943887/
- 3.Methylene Blue in Septic Shock: A Systematic Review and Meta-Analysis(opens PubMed in a new tab)Crit Care Explor · 2024 · PMID 38904978 · https://pubmed.ncbi.nlm.nih.gov/38904978/
- 4.Methylene Blue in the Treatment of Neuropsychiatric Disorders(opens PubMed in a new tab)CNS Drugs · 2019 · PMID 31144270 · https://pubmed.ncbi.nlm.nih.gov/31144270/
Sources cited on this page
Specific documents referenced by the numbered markers above. Each number matches the marker in the text.
- PubChem CID 6099(opens in a new tab)National Center for Biotechnology Information · pubchem.ncbi.nlm.nih.gov/compound/6099
Verify at
Publisher search links for Methylene Blue. These are places to check the information — they are not citations, so they are not numbered.
- DrugBank(publisher search, opens in a new tab)DrugBank Online · publisher search
- FDA-approved labeling (DailyMed)(publisher search, opens in a new tab)U.S. Food and Drug Administration · publisher search
- European Medicines Agency(publisher search, opens in a new tab)European Medicines Agency · publisher search
- NIH Office of Dietary Supplements(publisher search, opens in a new tab)National Institutes of Health · publisher search
- PubMed literature search(publisher search, opens in a new tab)National Library of Medicine · publisher search
- Wikipedia entry(publisher search, opens in a new tab)Wikipedia · publisher search
DoseRoutine compiles summaries from publicly available scientific and regulatory references. Always verify important decisions with a licensed clinician. How we source and review this information.
What is the short answer on Methylene Blue?
Plain-text summary, safe to quote verbatim:
Methylene Blue (MB) is a synthetic organic compound that belongs to the phenothiazine class. It is perhaps best known for its historical use as a dye for staining tissues and bacteria, and as a treatment for methemoglobinemia. Research on Methylene Blue focuses on cognition and mood and mitochondrial function.
Source: DoseRoutine — https://doseroutine.com/library/methylene-blue
Methylene Blue cheat sheet
DoseRoutine cheat sheet · Supplement
Methylene Blue
Methylene Blue (MB) is a synthetic organic compound that belongs to the phenothiazine class. It is perhaps best known for its historical use as a dye for staining tissues and bacteria, and as a treatment for methemoglobinemia.
Evidence
Strong
2 human randomized trials and regulatory approval on file.
Studied range
The brain-imaging trial used a single oral dose of roughly 0.5-4 mg/kg; the septic-shock trial infused 100 mg intravenously
Route
Oral in the cognition trial, intravenous in the critical-care trial
Frequency studied
Single dose in the imaging trial; three daily infusions in the septic-shock trial
Half-life
Roughly 5-6 hours
Timing
in the morning
Storage
Cool, dark, sealed
Prescription only (US)Methylene blue (ProvayBlue) is FDA-approved for methemoglobinemia, not for cognition or longevityIt is a monoamine oxidase inhibitor and can cause serotonin syndrome with serotonergic drugsContraindicated in G6PD deficiencyBrainMitochondria
Studied ranges, not dosing advice. Not medical advice — talk to a clinician. doseroutine.com/library/methylene-blue
Cite this page
Using this in an article, AI answer, or research note? Please attribute:
DoseRoutine. (2026). Methylene Blue — Overview, Benefits & Side Effects. Retrieved from https://doseroutine.com/library/methylene-blue
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