How to read PeptoKing
What a peptide is, how we decide an entry's status and evidence grade, and the rules every page follows.
What is a peptide?
A peptide is a short chain of amino acids joined end to end. Proteins are long chains, usually more than 50 amino acids and folded into a shape; peptides are shorter and often work as signals, telling a receptor somewhere in the body to switch something on or off. Your body makes thousands of them, including insulin, oxytocin and the gut hormone GLP-1.
Most peptide medicines are copies of natural signals, changed a little so they last longer. Semaglutide is GLP-1 with two swaps and a fatty tail that lets it ride on albumin in the blood, which stretches its life from minutes to about a week.
Point at a bead, or focus the chain and use the arrow keys, to name it. Pick a chemistry to highlight it.
Regulatory status
Every entry carries one status mark, decided from regulator records rather than marketing. When a medicine is approved in the United States or the European Union for any use, it is marked approved, even if people also use it off-label for something else.
- Approved
- Approved in the United States or the European Union for at least one use.
- Approved elsewhere
- Approved by another national regulator, not in the United States or the European Union.
- In clinical trials
- In registered human trials and not approved by any major regulator yet.
- Withdrawn
- Was approved in the US or EU, but the product has since been withdrawn or discontinued.
- Not approved
- No approval anywhere. Sold as a research chemical or compounded.
- Cosmetic ingredient
- Used in topical cosmetics, not regulated as a medicine.
Evidence grades
The grade describes the best human evidence for the main use people take it for. A licensed medicine can have strong evidence for diabetes and none for the anti-ageing claims made about it online; the entry says so in words.
- Strong
- Several large randomised controlled trials in people.
- Moderate
- At least one good randomised trial, or consistent smaller human trials.
- Preliminary
- Small human studies, pilots or observational data.
- Animal data only
- Almost everything known comes from animals or cells.
Residue colours
Beads are coloured by the chemistry of each amino acid's side chain. Non-standard building blocks, which chemists add to make a peptide last longer, are hatched. Mirror-image D-amino acids are written in lower case.
The rules
- Sourced or silent. Every claim traces to a label, a regulator, a trial registry, a peer-reviewed paper or a reputable news outlet.
- Educate, never enable. Dosing appears only for approved medicines, only as the label states it. We never publish protocols, stacks or sourcing for unapproved compounds.
- Real news only. Every news item is a real, dated event with a source you can check.
Our name is a peptide
PEPTOKING is a valid nonapeptide: proline, glutamic acid, proline, threonine, pyrrolysine, lysine, isoleucine, asparagine, glycine. The O is pyrrolysine, the rare 22nd amino acid, found in some archaea and bacteria. That is the chain in our logo.
Point at a bead, or focus the chain and use the arrow keys, to name it. Pick a chemistry to highlight it.
Not medical advice
PeptoKing explains what is known. It does not diagnose, treat or recommend. Research peptides sold online are not checked for purity or dose by any regulator, and several have been found contaminated or mislabelled.