Made in USA Methylene Blue: What the Label Does and Does Not Prove

"Made in USA" is a legal claim about where a product and its ingredients come from. It is not a quality grade. Under the FTC's Made in USA Labeling Rule, an unqualified claim means final assembly or processing happens in the United States, all significant processing happens in the United States, and all or virtually all ingredients or components are made and sourced in the United States. Nothing in that rule says the product is pure, potent, or free of heavy metals. Those things only show up in third-party lab testing.

• Unqualified means all or virtually all. Under 16 CFR 323.2, final assembly, all significant processing, and all or virtually all ingredients must be U.S.-made and U.S.-sourced.
• Look-alikes cover one step only. "Packaged in," "formulated in," "distributed by," and "cGMP facility in" each describe a single fact, not the origin of the powder inside.
• Only third-party lab testing shows quality. Look for published results from a named, independent lab with measured values.

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

The rule is short, and it is worth reading once. In 16 CFR Part 323, Made in USA Labeling, the FTC defines "Made in the United States" as any unqualified representation, express or implied, that a product is of U.S. origin. That includes words like "made," "manufactured," "built," "produced," "created," or "crafted" in the United States or in America. Section 323.2 then says it is an unfair or deceptive practice to label a product that way unless three things are true:

• final assembly or processing of the product occurs in the United States,
• all significant processing that goes into the product occurs in the United States, and
• all or virtually all ingredients or components of the product are made and sourced in the United States.

The FTC's own business guidance calls this the "all or virtually all" standard and says the product should contain no, or negligible, foreign content. A company making the claim needs a reasonable basis for it, meaning competent and reliable evidence, and it has to keep checking that the basis still holds. If the company starts sourcing parts overseas, the guidance says it must update its marketing (FTC, Complying with the Made in USA Standard).

There is also a middle lane. A qualified claim, such as "Made in USA of U.S. and imported parts," describes how much of the product is domestic. The FTC says even those claims need care, because they can still suggest more domestic content than a product really has.

Brands use a whole family of phrases that sound similar. They are not interchangeable. Each one describes a single fact, and the table shows what that fact is and what it leaves open.

Two notes on that table. First, the FTC says claims that a particular process was performed in the U.S. must be truthful, substantiated, and clearly refer to the specific process, so "packaged in" or "formulated in" should only ever be read as covering that named step. Second, the FTC guidance says a company's brand name or its U.S. headquarters does not by itself make a U.S. origin claim. Part 111 is also not an origin rule: it applies to anyone who manufactures, packages, labels, or holds a dietary supplement, including supplements imported into the United States (21 CFR Part 111, Current Good Manufacturing Practice for Dietary Supplements).

Even an honest "manufactured in the USA" line can leave you guessing about the ingredient that matters most. A capsule can be filled, packed, and labeled here while the methylene blue powder inside was produced somewhere else. Nothing on a standard supplement label requires a brand to say where each raw material came from, so the label alone will not answer it.

The FTC's guidance shows how it thinks about this. Whether raw materials count toward the "all or virtually all" test depends on how much of the product's cost they represent and how far removed they are from the finished product. Its examples are a gold ring, where imported gold defeats an unqualified claim because it is an integral component one step from the finished article, and a plastic clock radio case made from imported petroleum, where the claim can stand because the petroleum is far removed and a small part of the product.

None of this means imported raw material is bad or domestic raw material is good. Origin and quality are two different axes. A brand with overseas raw material and published third-party testing can be a safer buy than a brand with a proud flag on the bottle and no lab results.

Set the origin question aside and look at what you actually care about when a capsule goes into your body. None of the following is established by any origin phrase in the table above:

• Purity. How much of the powder is methylene blue, and what else is in it.
• Potency. Whether the milligrams on the label are the milligrams in the capsule.
• Heavy metals and microbes. Whether the product was tested for lead, arsenic, and other contaminants, and what the numbers were.

Only third-party lab testing speaks to those points: a report from a named, independent lab with measured values rather than a line that says "complies." Our guide on how to read a supplement lab report walks through each field, and is it really third-party tested covers how to check that a lab report is real. If you want the broader list of warning signs, see methylene blue quality red flags. And since "USP grade" often appears next to "Made in USA" on labels, what is USP grade methylene blue explains what that phrase does and does not mean.

1. Read the exact wording. Is it an unqualified "Made in USA," or a step-specific phrase like "packaged in" or "formulated in"? Match it against the table above.
2. Look for published third-party lab results. Check the brand's site for test reports from a named, independent lab.
3. Check what the report measures. Look for a test date and measured values, such as potency, heavy metals, and microbial results, rather than a line that says "complies."
4. Look for independent GMP verification. cGMP under 21 CFR Part 111 covers supplements whether they are made here or imported, so see whether an independent program, such as NSF, has verified the facility.

It is the same short list we would want a reader to run on us. Sources for all of it are in the references.

Our product pages state that the capsules are manufactured in the United States in an NSF GMP-verified, cGMP-compliant facility, and that our manufacturer follows 21 CFR Part 111.

That describes where the finished product is made and the quality system the facility works under. It is a statement about manufacturing, not about the origin of each ingredient.

The third-party lab reports we publish are on our certs page, and each one is labeled with the product it covers and its test date. Open one and check it against the four steps above. As always, read the adverse medications list and talk to your healthcare provider before using methylene blue.

Do not take methylene blue if you are currently using:

• SSRIs or MAOIs (the FDA label warns of serotonin syndrome)
• Any other serotonergic medication
• If you are pregnant, nursing, or have G6PD deficiency, speak with your healthcare provider first

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

Every Nutricel formula uses the same methylene blue. Third-party lab reports are on our lab tests page. Whether methylene blue fits you at all is a question for your healthcare provider.

If you and your provider decide it does, this is how our products differ:

Blue Boost is our core formula: 12mg of methylene blue per capsule.

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

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) alongside methylene blue.

Blue Remove combines zeolite, curcumin, and nattokinase with methylene blue.

Blue Liquid delivers USP-grade methylene blue in a dropper bottle for liquid format.

"Made in USA" answers one question: where did this product and its ingredients come from. It is a fair thing to care about, and it has a real legal standard behind it. It does not answer whether the capsule in your hand is pure, potent, or clean.

So use the label as a prompt, not a verdict. Read the exact phrase, then look for published third-party lab results from a named, independent lab. A brand that publishes those is showing its work.

FTC Made in USA Rule

FDA Manufacturing Rules

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.