A peptide is a short chain of amino acids — conventionally two to about fifty residues, joined by the same bond that builds proteins. The distinction from a protein is length and, usually, job: where proteins are machinery, peptides are mostly messages. Insulin, oxytocin and the hormone that triggers a growth-hormone pulse are all peptides the body already makes; most of the compounds in this library are laboratory copies, fragments or redesigns of signals like these.
Why researchers study them
Because a peptide is usually a copy of an endogenous signal, it tends to act on one receptor with high specificity — the message arrives where it was addressed. That precision is why peptides interest researchers studying tissue repair, metabolic signalling and hormone axes, and it is why the research literature for a single peptide often spans wildly different fields.
The same precision cuts the other way: peptides are fragile. Most survive neither the gut nor much time in the blood, which is why nearly everything here is studied as an injectable with a half-life measured in minutes or hours, and why handling — storage, reconstitution, cold chain — takes up a whole section of this site.
Research compound versus medicine
A handful of peptides crossed all the way into approved medicine — semaglutide, tesamorelin and teriparatide among them. The rest occupy a research-only space: no manufacturing standard applies, no dosing label exists, and no regulator has reviewed them for use in a person. "Research use only" is a legal category, not a formality, and it has two practical consequences.
- Nothing guarantees what is in a vial. The only evidence is a supplier's Certificate of Analysis, which is why this site teaches how to read one.
- No number anywhere is a dose for a person. Dosing tables on monographs record what published research used — a record, not an instruction.
How to read a monograph
Each compound page follows the same order: an overview, the research indications it has actually been studied for, molecular data, a dosing reference, interactions, and safety. Every indication carries an evidence grade from A (controlled human trials) down to D (cell culture and mechanism), paired with the effect size that was measured — two separate tokens, never averaged into a score. Where evidence is missing, the page says so instead of borrowing from a stronger claim.
Named blends and protocols — the recipes with marketing names — are recorded as their component peptides, because that is where the evidence lives.
Where to start
- Browse the library by category, or search with the ⌘K palette from any page.
- Open one monograph end to end — BPC-157 is a good first read — to see how the grading works.
- Read the evidence-grading guide before trusting any single claim.
- Keep the reconstitution calculator open the first time you work with a lyophilised vial.
Everything in this library describes research material. Nothing here is medical advice, and no figure on any page is a recommendation to dose a person.