We Lab-Tested 61 Methylene Blue Brands. Here's What We Found.

We built an independent water-and-lab testing database for methylene blue supplements, and as of July 7, 2026 we had tested 61 products out of 162 tracked. The result: only 22 (36.1%) passed both tests, while 39 (63.9%) failed for purity, dose, or both. Every Nutricel product in the database passed.

• 61 products independently tested so far, out of 162 methylene blue products we track overall.
• 63.9% failed for purity or dose. Most failures showed little or no detectable methylene blue in an independent lab assay. These were not labeling technicalities.
• All 6 Nutricel products passed both tests. Search the database yourself before buying any brand, including ours.

Important: The FDA warned in 2011 that methylene blue can cause serotonin syndrome with serotonergic psychiatric medications, including SSRIs and MAOIs. Review the full adverse medications list before use.

We built it because almost none of the brands publish independent testing. Interest in methylene blue has grown fast over the past few years, and dozens of new brands came with it. So we commissioned water tests and independent lab assays for as many methylene blue products as we could get our hands on, and we published every result, pass or fail, in one place.

Methylene blue has known drug interactions, which the FDA warned about in 2011. A mislabeled or underdosed product wastes your money, and it also means you do not know how much you are taking.

Each product goes through up to two checks:

• Water test. We dissolve the product in water and observe the color. Genuine methylene blue produces a deep, vivid blue. A weak, faint, or off-color result signals a low or diluted dose.
• Lab test. We send the product to an independent third-party lab for assay, which measures the actual methylene blue content in milligrams and compares it against the amount claimed on the label.

Most failures were not close calls. A number of products showed little or no detectable methylene blue against label claims well above zero, so the water test and lab assay found almost none of what the label promised.

It usually looks like one of two things. Across the 39 products that failed, we see these patterns:

• No detectable methylene blue. The lab assay finds little to no active ingredient at all, even though the label lists a specific milligram dose. The water test usually confirms this too: instead of the characteristic deep blue, the solution comes out pale, gray, or barely tinted.
• Underdosed relative to label. The product does contain real methylene blue, but the lab-measured amount falls meaningfully short of what the label claims. These can sometimes pass the water test and still fail the lab assay, which is why we require both.

Blue Boost, along with every other Nutricel product in the database, passed the water test. Blue Boost's methylene blue content is also confirmed by a published third-party lab report, posted on our lab reports page.

We built the program and we sell the products, so take our result with that in mind. That is why the water test result, lab-detected dose, and verdict for the other five Nutricel products are in the database itself, not just summarized here. Check them yourself alongside every other brand.

Start by checking you found the exact product, then test it and look for its lab report. If your brand shows an Avoid verdict, or it is not listed, here is what we would do:

• Check the exact product name and format. Brands often sell multiple methylene blue products (capsules, liquid, blends), and a passing or failing result for one does not automatically apply to another.
• Run your own water test. Dissolve a single dose in a glass of water. A deep, vivid blue is a good sign; a pale, weak, or grayish tint suggests a diluted or underdosed product.
• Look for a published lab report. Brands that test their products usually post third-party lab results on their own site. A general quality statement with no results behind it is a reason to be cautious.
• Talk to your healthcare provider if you take an interacting medication. If you cannot verify what is in a product and you are on an SSRI, MAOI, or other serotonergic medication, stop and check with your provider first.

The full database lets you search by brand name, filter by product type or seller country, and see the verdict, Recommended, Avoid, or Not Tested, for each product, along with its water test result, lab test result, and claimed dose. Before you buy or reorder any methylene blue product, search for it by name and check its verdict.

All six Nutricel products below passed both the water test and the independent lab assay described above. Here is which one fits your goal:

See the full product grid above or below to compare pricing and go directly to any product page.

Do not take methylene blue, from any brand, if you are currently using:

• SSRIs or MAOIs (the FDA warns of serotonin syndrome)
• Any serotonergic medication

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

Most of the methylene blue products we tested, nearly two out of three as of July 7, 2026, failed basic purity or dose checks, and a number of them had little to no detectable methylene blue. The database is free to search and the dataset is free to download, so you do not have to guess. Search your brand before your next order. If you are choosing a new one, every Nutricel product passed the water test, our capsule lab reports are published, and we would still tell you to check that yourself.

• Nutricel. Methylene Blue Lab and Water Test Database. Full methodology and per-product results, updated July 7, 2026.
• U.S. Food and Drug Administration. Drug Safety Communication: methylene blue and serotonergic drugs (archived).

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. Every figure in this piece comes directly from Nutricel's public lab test database, linked in the references above. Sam is not a medical professional, and this article is intended as education rather than medical advice. Always speak with your healthcare provider before starting any supplement.