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Types of peptides: a map of the Library
Rather than one long list, peptides split cleanly into how they're used and how strong the evidence is for each use. This page is the map — every branch links to the full page.
In brief
Should you care? This page exists to be a starting point, not a destination — use it to find the specific page relevant to whatever you actually came here to check.The short version
- By route: topical, oral, injectable/prescription.
- By cosmetic function: signal, carrier, neurotransmitter-inhibitor, enzyme-inhibitor.
- By evidence: every page on this site carries a grade, A to D, explained on our standard.
By route of use
- Topical (skincare): copper peptide, Matrixyl 3000, Argireline, palmitoyl tripeptide-1.
- Oral / ingestible: collagen peptides.
- Prescription / injectable, approved: semaglutide, tirzepatide — see the legal status tracker.
- Injectable, unapproved / grey-market: BPC-157 and similar — see BPC-157’s legal status and vendor red flags before considering any of these.
By cosmetic function
Within topical skincare specifically, peptides split further by mechanism — signal, carrier, neurotransmitter-inhibitor and enzyme-inhibitor. The full breakdown is here, with a worked example of each.
By evidence grade, across the whole Library
| Grade | Examples in this Library |
|---|---|
| A | Copper peptide, Matrixyl 3000, semaglutide, tirzepatide |
| B | Argireline, palmitoyl tripeptide-1, collagen peptides |
| C | Thymosin alpha-1 (outside its approved indications) |
| D | BPC-157, TB-500, epitalon, MOTS-c |
The grade describes evidence strength for the way each compound is actually being sold and used — not the compound’s inherent worth. Full grading methodology here.
References
- Grades and categorisations drawn from the individual Library pages linked above.