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 have tested 61 products so far, 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, not just a labeling technicality.
• All 6 Nutricel products passed both tests. Search the database yourself before buying any brand, including ours.

Important: Methylene blue has documented interactions with serotonergic medications including SSRIs and MAOIs. Review the full adverse medications list before use.

Interest in methylene blue has exploded over the past few years, and dozens of new brands have entered the market with it. Almost none of them publish independent testing. 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 a narrow safety margin and known drug interactions. Buying a mislabeled or underdosed product is not just a waste of money; it can mean taking the wrong amount of an active compound without knowing it.

Every product in the database goes through up to two independent 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 at all against label claims well above zero, meaning the water test and lab assay found essentially none of the active ingredient the label promised.

Blue Boost, along with every other Nutricel product in the database, Blue Shroom, Blue Renew, Blue Immune, Blue Remove, and Blue Liquid, passed both the water test and the independent lab assay. Blue Boost's lab-detected dose came in at 12.83 mg against its 12 mg label claim, about 6.9% over label, confirming full potency.

Nutricel is the only full product line in the database of over 160 methylene blue products where every single product passed both tests.

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.

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

• SSRIs or MAOIs (risk of serotonin syndrome)
• Any serotonergic medication

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

• 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.