What “research use only” and a COA really mean

What does “research use only, not for human consumption” mean legally?

In the US, the label doesn't decide what a product is. Under federal law, something is a drug if it's intended to treat or prevent disease, or to affect the structure or function of the body³. FDA works out intended use from the whole picture: labels, advertising, websites, other promotion and why buyers buy it³.

FDA applied this in an August 2026 warning letter to a peptide seller. The letter says that “despite statements on your product labeling marketing your products ‘for research use only’ and ‘not for human or veterinary use,’ evidence obtained from your website establishes that your products are intended to be drugs for human use”¹. Selling bacteriostatic water to mix the peptides counted as part of that evidence, and FDA treated the water as a drug too¹.

FDA has also warned companies selling semaglutide, tirzepatide and retatrutide “falsely labeled” for research. It says these were sold straight to consumers with dosing instructions, are of unknown quality, and may be harmful².

Is “research use only” legal in the UK and Canada?

In Canada, Health Canada says plainly that “For Research Use Only – Not for Human Consumption” labeling does not make products legal or exempt from regulatory requirements⁴. It generally regulates injectable peptides as prescription drugs, and calls unauthorized drug products illegal⁴.

In the UK, the MHRA decides whether a product is a medicine from its claims, its ingredients and how it's presented, including on websites, on social media and in customer reviews⁶. A substance used to change how the body works by a drug-like action can count as a medicine whatever the label says⁶.

What is a certificate of analysis (COA) for a peptide?

A COA is a document listing the tests run on one batch of a substance and the results. It covers the batch that was tested, not every vial sold under the same name.

Nothing sets which tests a research peptide COA has to include. When FDA looked at COAs for BPC-157, most showed only a purity result, with no impurity limits, no endotoxin or microbial testing, and no residual solvent testing⁷. One COA listed purity of 97.8%, but FDA said the impurity profile was unclear because the impurities weren't identified⁷.

What does a COA show, and what doesn't it show?

Each test answers one question. A high purity number answers only the purity question, which is why a vial can pass on purity and still fail on endotoxin or sterility.

FDA's reviewers also flagged a naming problem. “BPC-157” is a common name, not an official drug name, and FDA has found different salts and related compounds sold under the same name⁷. A COA for one form doesn't describe another.

What did testing of peptides bought online find?

Independent testing has found wrong amounts, low purity, toxic metals and bacteria in peptide products sold online. The studies are small, and most tested GLP-1 drugs or falsified peptide medicines rather than BPC-157 or TB-500. We didn't find a peer-reviewed study that bought and tested BPC-157 or TB-500 products.

The semaglutide study is a useful example. The vials claimed 99% purity, contained more semaglutide than the label said, grew no microbes, and still all had endotoxin⁹. A single purity number would have hidden all of that.

Why does contamination matter more for injected peptides?

Injections go straight into the body, sometimes into the bloodstream, and skip some of the body's defenses against toxins and germs¹. Health Canada says injecting a contaminated product can cause serious infections, hospitalization and, in severe cases, life-threatening sepsis⁵.

For where specific peptides stand with regulators, see BPC-157 legal status and the retatrutide page.