Plain-English explainers
What is…
Quick, plain-English answers to the most-searched questions in metabolic peptide research. Click through for the full molecule profile when you want the depth.
How to use the “what is…” explainers
Each page on this hub answers a single “what is X?” question in plain UK English, at a length and depth pitched to the reader arriving from a general search: what the molecule is, what it does at a high level, how it's used, and where the full scientific profile lives on the site. These are entry-point pages, not depth pages.
When you want the depth — mechanism, discovery history, published trial evidence, safety profile, UK regulatory status, related conditions — the corresponding molecule profile at /peptides is the destination. Every “what is…” page links out to the matching profile in its closing paragraph. The site's brand-name landings live at /brands; the trial pages at /trials.
None of the “what is…” pages provide dosing schedules, prescribing recommendations, supplier information, or clinical triage. Where a medicine is UK-licensed, any actual use is via a qualified UK prescriber following appropriate clinical assessment.
What is tirzepatide?
The dual GIP/GLP-1 agonist sold in the UK as Mounjaro — what it is, who developed it, what it does.
What is retatrutide?
The triple GLP-1/GIP/glucagon agonist with the largest Phase 2 weight-reduction signal yet recorded.
What is semaglutide?
The GLP-1 monoagonist behind Ozempic, Wegovy and Rybelsus — three brands of the same molecule.
Semaglutide brands and drug class
Which UK brand names contain semaglutide (Ozempic, Wegovy, Rybelsus) and what drug class it belongs to.
What is GLP-1?
The endogenous hormone that gives this entire class of medicines its name — what it does in the body.