Reference
Compound classes
The 12 families behind the peptide market. Each page explains what the family is, how its evidence looks as a whole, and lists every member with its grade — so a compound you have never heard of can be placed at a glance.
GLP-1 and incretin agonists
The obesity and diabetes drugs. The best-evidenced compounds on this site, and the only family with cardiovascular-outcome trials behind it.
GHRH analogues
Synthetic versions of the hypothalamic hormone that tells the pituitary to release growth hormone. One narrow approval; one withdrawn diagnostic; one abandoned programme.
GH secretagogues (GHRPs)
Ghrelin-receptor agonists that trigger a growth-hormone pulse. Good diagnostic tools — and one oral member, MK-677, with a year-long trial showing a little more lean mass and no less fat.
Growth hormone, IGF-1 and growth factors
The hormone, its downstream mediator, two fragments, and a myostatin blocker. One approved medicine, three laboratory reagents, and one properly tested failure.
Tissue-repair peptides
The healing peptides of the internet. Consistent animal results, one tripeptide with modest topical evidence, and no controlled human trial of injected use for any of them.
Melanocortin agonists
Four analogues of the same pigment hormone. Three became approved medicines — for low sexual desire, a rare light-sensitivity disease, and genetic obesity; one stayed a grey-market tanning injection with documented harms.
Mitochondrial, antioxidant and longevity compounds
The longevity market's compounds: mitochondrial peptides, a coenzyme, an enzyme inhibitor, an antioxidant. One approval for an ultra-rare disease; otherwise mouse data and observation.
Nootropic and sleep peptides
Cognition, anxiety, stroke and sleep. Three are Russian-registered and unreplicated; two are animal-brain extracts — one with Cochrane reviews against it, one with a single Russian trial; one has never been given to a human; one was tested in the 1980s and mostly did not work.
Reproductive and neuroendocrine hormones
Five reproductive-axis hormones and analogues with genuine medical licences — including the one that switches the axis off — and off-label reputations their trials do not support.
Bone and endocrine peptide medicines
Settled peptide medicines, included as reference points: two that build bone, one that switches growth hormone off, one retired by its own safety data, one banned in sport as a masking agent, and the original: insulin.
Peptides sold as supplements
The peptides most people actually take: collagen powder and carnosine capsules. Legal, safe, heavily trialled by their makers — and with effects that shrink when independent trials are counted.
Immune, antimicrobial and repair-signal peptides
A thymic immune modulator that failed its largest trial, the human antimicrobial peptide with two wound-healing trials, a gut hormone whose 461-person COVID trial found nothing, and an erythropoietin fragment with one small positive phase 2.
Open data
The taxonomy is published as JSON alongside the compound records, CC BY 4.0. Every compound belongs to exactly one family; the build fails otherwise.