Retatrutide
Also known as: LY3437943, GGG tri-agonist, triple agonist (GIP/GLP-1/glucagon receptor agonist)
Retatrutide, also identified in research as LY3437943, is an investigational peptide developed by Eli Lilly. It is designed to activate three receptors: the GIP receptor, the GLP-1 receptor, and the glucagon receptor. This sets it apart from single-target GLP-1 agonists and from the dual GIP/GLP-1 agonist tirzepatide. It has not completed regulatory review and remains an experimental compound.
How it works
Published research describes retatrutide as an agonist at three receptors tied to appetite, insulin secretion, and energy metabolism: GIP, GLP-1, and glucagon. Investigators suggest the glucagon receptor component may affect energy expenditure and liver fat in addition to the appetite and glucose pathways linked to GIP and GLP-1. These are described mechanisms under study and not a promise of any result.
Researched uses
- studied for chronic weight management in adults with obesity or overweight
- studied for type 2 diabetes glycemic control
- studied for metabolic dysfunction-associated steatotic liver disease (MASLD/NAFLD)
- studied for reduction of liver fat content
- studied for cardiometabolic risk factors such as blood pressure and lipids
Investigational and NOT FDA-approved for any use. Retatrutide is available only through Eli Lilly-sponsored clinical trials. Under US federal law it cannot be legally compounded, and no legitimate prescription pathway exists outside of enrollment in an authorized clinical trial. Products marketed online as retatrutide "for research use only" are unregulated, fall outside the licensed pharmacy system, and are not approved medicines. This contrasts with semaglutide (FDA-approved as Ozempic and Wegovy) and tirzepatide (FDA-approved as Mounjaro and Zepbound), which are licensed branded products.
Retatrutide providers compared
Providers that have passed our rubric review are listed first, then ordered by the total cost of a 3-month protocol. We average every cost to a standard 3-month protocol, which our medical advisors consider the best basis for comparing cost and value, and the headline figure folds in any one-time consult or provider-review fee plus three months of membership. Use the calculator below to adjust the length and see the same total broken out.
| Provider | Sourcing | What's included | Verified | Visit provider | |
|---|---|---|---|---|---|
| No provider in this directory currently lists a published price for this drug. | |||||
We average every cost to a standard 3-month protocol, which our medical advisors consider the best window for comparing cost and value. Monthly plans are multiplied by 3 and 3-month programs are taken as billed; each provider's own sticker price and cadence are shown underneath.
The headline figure is the total 3-month cost: the medication plus any one-time consult or provider-review fee (for example RxPepsDirect's $39) and three months of any membership fee. Where a fee is not published we fold in what is known and flag that other fees may apply.
Per-vial providers are averaged to a 3-month protocol at roughly one vial per month (3 vials), marked "est.", with the per-vial price shown underneath. Actual vial count depends on your dose and protocol.
Prices are gathered from each provider's public pages. The "Verified" date is when we last checked the provider's sticker price; for per-vial providers it is the vial price that was verified, not the averaged 3-month total.
Safety notes
Retatrutide is still in clinical development, so its full safety profile is not established. Trials have reported gastrointestinal effects such as nausea, vomiting, diarrhea, and constipation, in line with the incretin drug class, with dose-related patterns still under study. Long-term safety and rare risks remain unproven pending larger trials. Anything sold outside the licensed pharmacy system carries added risk because identity, purity, dose, and sterility are unverified and not subject to FDA oversight.
In the news
- Retatrutide is exploding online. Is it legal? Sorta. The Washington Post
Reporting on surging online demand for retatrutide, an investigational triple-agonist weight-loss drug, and the murky legality of buying it outside its clinical-trial-only availability.
- Retatrutide Results Spark Questions about How Rapid Weight Loss Affects the Body Scientific American
Coverage of retatrutide's phase-2 weight-loss results and the open questions about rapid weight loss, from a peer-reviewed-adjacent science outlet.
- Inside the booming, gray-market world of injectable peptides The Hill
Reporting on the gray market for research-use-only injectable peptides sold outside the licensed pharmacy system, and the associated health concerns.
Retatrutide questions
How much does Retatrutide cost?
No licensed provider in this directory currently publishes a price for Retatrutide. This page will list verified prices with their sources if that changes.
Is retatrutide FDA-approved?
No. Retatrutide is investigational and has not been approved by the FDA for any use. It is currently available only within Eli Lilly-sponsored clinical trials.
Can I get retatrutide from a compounding pharmacy with a prescription?
No. Under US federal law retatrutide cannot be legally compounded, and there is no legitimate prescription pathway outside of an authorized clinical trial. Products sold online as retatrutide are unregulated and sit outside the licensed pharmacy system.
How does retatrutide compare to semaglutide and tirzepatide in terms of availability and cost?
Semaglutide and tirzepatide are FDA-approved branded medicines with established pricing and licensed distribution. Retatrutide has no approved status, no legitimate market price, and no legal supply outside clinical trials, so any cost quoted by an online seller reflects an unregulated product rather than an approved medication.
Related reading
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