Editorial method

The evidence rating is the whole product, so the rules behind it are public and fixed.

Sources, in order

Regulatory filings and approved labels come first, then registered trials with published results, then peer-reviewed literature. Vendor materials — product pages, certificates supplied by sellers, marketing claims — are never a source for anything published here.

Route counts

Evidence generated for one route of administration does not carry to another. A compound with human topical data is described on those terms and is never credited for injection. This single rule accounts for a large share of the misleading claims in this market.

What the ratings mean

• Extensive — large randomised trials with hard endpoints, generally approved.
• Substantial — good human trial evidence, often narrow in population or indication.
• Moderate — real human data, but limited in size, route, or relevance to how the compound is used.
• Limited — small or industry-funded human studies, thin replication.
• Preclinical — animal or in-vitro work only, with no completed human evidence.

How we're funded

Some links on this site earn a commission when you buy through them. That never affects a compound's rating, its category, or a single word written about it. See the disclosure page for the full position.

Corrections in public

When we get something wrong we fix it with a dated note on the page rather than quietly editing the text. If you spot an error, tell us and we will look at the primary source.