Why Peptide Names Look Like That
BPC-157, GHK-Cu, Semaglutide, MOTS-c, SNAP-8 — five naming systems in five names, each carrying different information.
Peptide names are a mess of conventions layered on top of each other. BPC-157, TB-500, GHK-Cu, Ipamorelin, Semaglutide, MOTS-c, SNAP-8 — six naming systems in six names. Each carries information once you know which system it belongs to.
Fragment names: a number after a hyphen
BPC-157, TB-500, AOD-9604. The number is usually a laboratory or development code rather than a meaningful measurement, but the pattern signals a compound derived from or related to a larger parent protein.
BPC-157 is a 15-residue sequence related to a gastric protein designated Body Protection Compound. TB-500 corresponds to a fragment of thymosin beta-4. The names encode a research lineage, not a structure — which is why the sequence, not the name, is what a certificate must confirm.
Composition names: letters that are the sequence
GHK is glycyl-histidyl-lysine — the name is the sequence in single-letter code. KPV is lysine-proline-valine. GHK-Cu adds the copper ion the peptide chelates.
This convention only works for very short peptides, which is exactly where you see it. It is also the most informative naming system in use: the name tells you the molecule.
Pharmaceutical stems: -tide, -relin, -relix
The World Health Organization assigns International Nonproprietary Names using standardised stems, so the ending of a drug name carries real classification information:
| Stem | Meaning | Examples |
|---|---|---|
| -tide | Peptide | Semaglutide, tirzepatide, liraglutide |
| -relin | Releasing-hormone agonist | Tesamorelin, ipamorelin, sermorelin |
| -relix | Releasing-hormone antagonist | Cetrorelix, degarelix |
| -glutide | GLP-1 analogue | Semaglutide, dulaglutide |
| -mab | Monoclonal antibody (not a peptide) | — |
So a name ending in -relin tells you the compound acts as an agonist at a releasing-hormone receptor, and -relix tells you it blocks one. Ipamorelin and tesamorelin share the stem despite acting at completely different receptors — the stem describes the functional class, not the target.
Class-plus-number codes
GHRP-2, GHRP-6 — growth hormone releasing peptide, numbered by development order. CJC-1295 — a company code from ConjuChem. SNAP-8 — a marketing name for acetyl octapeptide-3, itself a cosmetic-ingredient designation.
Numbers in these names carry no chemical meaning. GHRP-6 is not “more” than GHRP-2.
Biological-origin names
MOTS-c — mitochondrial open reading frame of the twelve S rRNA type-c. DSIP — delta sleep-inducing peptide, named for an observed effect. Epithalon — from the epithalamus, its tissue of origin. These describe where the peptide came from or what was first observed, not what it is.
Why any of this matters practically
Two reasons.
Names are not unique. The same molecule appears under several names — acetyl octapeptide-3, SNAP-8 and its INCI designation are one compound. Comparing suppliers means comparing sequences and masses, not names.
Names are not verifiable. A certificate confirming “BPC-157” confirms nothing unless it states the sequence and a mass consistent with it. The name is a label; the sequence and mass are the claim.
Our guide to reading peptide sequences covers the notation, and the certificate guide covers what a document has to state to mean anything.
All products and information referenced are for in-vitro research and laboratory use only. Nothing here is medical advice, and no therapeutic claim is made or implied.