GLP-1 medications, explained independently
GLP-1 receptor agonists are a class of medications — including semaglutide and tirzepatide, sold under brand names such as Ozempic, Wegovy, Mounjaro, and Zepbound — used to treat type 2 diabetes and, increasingly, obesity. This section is your independent starting point for understanding them.
The short answer
GLP-1 is a hormone your own gut releases when you eat. It tells the pancreas to release insulin, slows how fast the stomach empties, and turns down appetite. A “GLP-1 medication” — properly, a GLP-1 receptor agonist — is a drug built to imitate that hormone and, crucially, to last far longer than it does.
Your own GLP-1 is broken down within minutes. The medications resist that breakdown and keep acting for days, which is why most are injected once a week rather than taken with meals. Everything else in this section follows from that one difference.
What GLP-1 is, in one pass
- The hormone. Glucagon-like peptide-1, an incretin released by cells in your intestine when food arrives.
- The class. GLP-1 receptor agonists — medicines that activate the same receptor, more strongly and for much longer.
- The molecules. Semaglutide, tirzepatide, liraglutide, orforglipron. Tirzepatide also acts at a second receptor, GIP.
- The brand names. Ozempic, Wegovy, Rybelsus, Mounjaro, Zepbound, Saxenda, Foundayo — one molecule can carry two brand names when it is approved for two different uses. See how those three levels fit together.
- What they treat. Type 2 diabetes and chronic weight management, with one product also approved for obstructive sleep apnoea.
- How you take them. A weekly injection or a daily tablet — both are real, and both need a prescription. See the format comparison.
The mechanism behind all of it — the four things these drugs do, and why the same four cause the side effects — is set out with sources in how GLP-1 medications work.
Each guide is written to a single evidence standard and sourced to the recognised authorities, with every page stating its clinical-review status openly. See how we work in our Editorial Policy, or browse the authorities we draw from.
Published guides
- How GLP-1 medications workThe four mechanisms — and why they explain the side effects too.
- GLP-1 statistics, sourced and datedUsage, trial efficacy, side-effect rates, spending, and persistence — every figure cited.
- GLP-1 glossaryEvery term, defined and searchable — drug names, dosing, side effects, compounding, and more.
- Drug referenceEvery approved product — molecule, approved use, form and published price.
- Cost and insurance coverageFind your cost pathway and the savings programmes you qualify for.
- The cheapest way to get a GLP-1Every route priced side by side, with telehealth membership fees added to the medication.
- Side effects: common vs. seriousWhat settles on its own, and what needs urgent care.
- Is GLP-1 safe?Safe compared to what, over how long — and where the evidence stops.
- ConstipationWhy it happens and what actually helps.
- Hair lossUsually the weight loss, not the drug — and usually temporary.
- Dosing and titrationWhy doses start low and climb slowly.
- Injection sites and rotationWhere to inject, how to rotate, what to avoid.
- Find a providerA data-rich, unranked directory of telehealth GLP-1 providers.
- Get matched to a providerAnswer 4 questions and see which directory providers actually fit — free, no referral fee.
- What to eat on GLP-1What the body-composition trial data actually shows, plus a protein target.
- Sample meal planA worked example of hitting a 100–130g protein target.
- What to eat, what to go easy onThe do/avoid pattern for managing a slowed stomach.
- Microdosing: what the evidence showsNo trial has tested it, and AACE doesn't support it — the honest answer.
- How microdosing is actually doneSupervised vs. self-directed use, and the real measurement risks.
Coming next
These are mapped, unwritten, and each has a stated reason it is not done yet. The full map — including the subjects we have decided not to write — is on what we cover and what we don’t.
- Whether GoodRx and discount cards work on a GLP-1. Not written, and on current evidence not writable to this site's standard. The rule here is that a price is read from the seller's own page on a stated date. Both major discount-card sites are behind commercial bot protection — GoodRx returns a PerimeterX challenge, SingleCare a DataDome one — and we will not defeat a CAPTCHA to take data a site has said it does not want taken. That is a decision rather than a delay: the remaining routes are a human reading the sites by hand and recording what they saw, or citing a third party who did. Until one of those happens this stays a gap, because the alternative is a page of plausible-sounding generalities about prices nobody here has seen.
Not medical advice
These guides are general education, not a substitute for advice from your own healthcare provider. Always talk to a qualified clinician about your specific situation before starting or changing a medication.