Methylene Blue Pee: Blue, Green, or No Color?

Whether methylene blue turns your urine blue depends on your body, your dose, and your hydration level. Blue urine is normal. Clear urine is also normal. Neither tells you whether the supplement is working.

That holds for capsules and drops alike, including Nutricel's Blue Boost (12mg per capsule) and Blue Liquid (1%).

• Methylene blue turns urine blue or green when the kidneys excrete it in its oxidized (pigmented) form. When your body converts it to leucomethylene blue, a colorless, reduced form, before excretion, no color change occurs.
• In a human oral dosing study by DiSanto and Wagner (1972), about 78% of methylene blue excreted in urine appeared as leucomethylene blue, so most of what showed up in urine was colorless.^[1]
• Urine color is not a measure of effectiveness. The color tells you about the dye leaving your body, not about what it did inside your cells.

Important: The FDA label for methylene blue injection warns about serotonin syndrome with SSRIs, MAOIs, and other serotonergic medications. Review the full adverse medications list before use.

Methylene blue is a water-soluble dye. When your kidneys filter it out of the bloodstream, any portion still carrying its blue pigment tints your urine blue or green on the way out. That is the whole explanation.

It does not always happen. Your body converts much of the methylene blue into a colorless form called leucomethylene blue before it is excreted. When that conversion keeps up, no color shows. StatPearls lists blue-green urine as an expected effect of methylene blue, and not seeing it is normal too.

Methylene blue is absorbed through the gastrointestinal tract and enters the bloodstream, where it distributes into tissues and cells. The NIH-hosted review "From Mitochondrial Function to Neuroprotection" describes methylene blue acting as an electron carrier in the mitochondrial electron transport chain, which is why researchers study it for cellular energy and for its role in helping reduce oxidative stress.

As part of this process, methylene blue accepts electrons and shifts from its blue, oxidized form into a colorless, reduced form called leucomethylene blue. That switch is part of how the compound behaves, not a sign it has broken down. It also means some of the methylene blue you pass in urine has no color left. DiSanto and Wagner (1972) gave people an oral dose and measured what came out: of the 74% of an oral 10mg dose recovered in urine, an average of 78% appeared as leucomethylene blue, not as the original blue compound.^[1] It is an older study, but it is the clearest human data we found on this question, and it says most of what the kidneys filter out is already colorless.

Figures drawn from the human oral dosing study cited in the references below.^[1] Individual results vary with hydration, dose, and metabolism.

No. Methylene blue does not always turn urine blue. Whether a color change appears depends on the balance between two competing processes: how quickly your kidneys filter and excrete the compound versus how quickly your cells reduce it to leucomethylene blue. If reduction outpaces excretion, there is little to no pigment left by the time the compound reaches your urine. Two people taking the same supplement the same way can see completely different results, and both are normal.

Several factors influence which outcome you see. At lower doses, the concentration of colored compound in circulation may simply be too low to visibly tint urine. If you are well-hydrated, the added fluid dilutes the pigment to the point where the tint becomes faint or invisible. How fast your liver and kidneys handle the compound can also matter, and people vary a lot.

When color does appear, it typically shows up within 2 to 6 hours of taking methylene blue and may persist for several hours depending on dose and hydration. At standard supplemental doses the effect typically resolves within a day or two.^[1]

Urine color does not tell you whether methylene blue is working. A lot of people assume no blue means no effect, but blue urine is simply the dye being excreted. The color and anything happening in your mitochondria are independent processes.

You can see no color and still have taken the full amount on the label. You can also see plenty of color and learn nothing about what it did. Urine color should not be used as a marker of efficacy. What we would look at instead is the lab report, the label, and whether you take it the same way each day.

The one case where no color is a warning: a product with little or no methylene blue in it will not tint anything either, and you cannot tell that from the toilet. Look for supplements with independent third-party lab testing from a credentialed lab, not just a manufacturer-issued lab report. Verify that results include actual content verification, with purity and dose confirmed, rather than a generic pass/fail.

We publish finished-product lab reports for our capsule formulas, with heavy metals and microbial safety testing by independent third-party labs. You can open them on the Nutricel certifications page.

Methylene blue is not for everyone. The FDA label for methylene blue injection (Provayblue) carries a boxed warning about serotonin syndrome with serotonergic drugs, because methylene blue inhibits monoamine oxidase. We apply that caution at supplement amounts too.

Do not take methylene blue if you are currently using:

• SSRIs or MAOIs (the FDA label warns of serotonin syndrome)
• SNRIs or other serotonergic medications such as tramadol, trazodone, or bupropion
• Blood pressure medications
• St. John's Wort, 5-HTP, or SAMe

It is also not for pregnant or nursing women. And the Provayblue label warns that methylene blue can cause hemolytic anemia in people with G6PD deficiency, so they should not take it.

Review the full adverse medications list and consult your healthcare provider before starting methylene blue in any form.

Every Nutricel product uses USP-grade methylene blue, and is made in the United States in an NSF GMP verified facility. Lab reports for our capsule formulas are published on the lab tests page. The difference between them is what goes in alongside the methylene blue.

Blue Boost is our core formula: 12 mg of methylene blue per capsule with Vitamin C Ester and organic cacao. If you mainly want methylene blue itself, start here.

Blue Immune combines methylene blue with copper, NAC, grass-fed beef liver, and vitamins A, C, and E for cellular and immune function support.

Blue Shroom pairs methylene blue with six organic mushroom extracts including lion's mane, reishi, cordyceps, chaga, shiitake, and turkey tail.

Blue Renew is built around GlyNAC (glycine and N-acetyl cysteine), studied for supporting glutathione levels and brain function in aging populations.

Blue Remove combines zeolite, curcumin, and nattokinase.

Blue Liquid is USP-grade methylene blue in a dropper bottle (1%, 10 mg per mL), for people who prefer liquid and want to adjust in small steps.

Whether your urine changes color or stays clear after taking methylene blue, both outcomes are normal. The color reflects how your body processed and excreted the compound. It is not a test of whether it is working.

Factors like metabolic reduction into leucomethylene blue, your kidney's excretion rate, hydration, and dose all influence the result. If you want to know what is in your capsule, read the lab report, not the toilet.

Always choose a methylene blue supplement backed by independent third-party lab testing from a credentialed lab. View Nutricel's published test results on the certifications page.

Pharmacokinetics and Excretion

Mitochondrial Function

Further Reading

Sam Carlson, Marketing Developer at Nutricel

Sam is a marketing developer at Nutricel who writes the Nutricel Insights series to help our customers understand methylene blue and make informed choices, translating the published research into plain language. Sam is not a medical professional, and these articles are intended as education rather than medical advice. Every figure in this piece is tied to the studies listed in the references, and you should always speak with your healthcare provider before starting any supplement.