FDA has not approved retatrutide for any condition. FDA also states that retatrutide cannot be used in compounding under federal law. In Eli Lilly’s May 2026 sponsor-reported phase 3 topline results, the most common adverse events were nausea (up to 42.4% at the 12 mg dose), diarrhea (up to 34.1%), constipation (up to 26.1%), and vomiting (up to 25.3%). These figures come from the company’s press release, not a peer-reviewed publication. The full clinical picture is not yet public.
FDA approval: None. Retatrutide has not been found safe and effective for any condition.
Phase 3 trial: TRIUMPH-1 completed (2,335 enrolled, NCT05929066). No registry results posted.
Public data: Sponsor topline release only (May 21, 2026). No peer-reviewed phase 3 paper yet.
Compounding: FDA states that retatrutide cannot be used in compounding under federal law.
Retail products: Any product sold directly to consumers as retatrutide is unapproved.
What retatrutide is and why it matters
Retatrutide is an investigational triple hormone receptor agonist that activates GIP, GLP-1, and glucagon receptors. Eli Lilly is developing it for obesity and related conditions.
The drug attracted attention after phase 2 results published in the New England Journal of Medicine in 2023 reported a least-squares mean weight reduction of 24.2% at 48 weeks for the highest dose group. That trial was randomized, double-blind, and placebo-controlled with 338 adults over 48 weeks. It was peer-reviewed and published, but small and Lilly-supported.
TRIUMPH-1 enrolled 2,335 participants, almost seven times as many as the phase 2 trial, and ran for 80 weeks with an extension to 104 weeks for participants with a baseline BMI of 35 or higher. On May 21, 2026, Lilly issued a press release summarizing what it called positive topline results. That release is the only public source of phase 3 data on retatrutide as of July 22, 2026.
Phase 3 adverse events: what the topline release shows
The table below reproduces adverse-event rates from Lilly’s May 21, 2026 topline release for the TRIUMPH-1 trial. Every figure is sponsor-reported. These numbers have not been independently verified or published in a peer-reviewed journal. The full safety dataset, including serious adverse events, laboratory abnormalities, and subgroup analyses, is not yet available.
| Adverse Event | Retatrutide 4 mg | Retatrutide 9 mg | Retatrutide 12 mg | Placebo |
|---|---|---|---|---|
| Nausea | 28.6% | 38.4% | 42.4% | 14.8% |
| Diarrhea | 25.2% | 34.1% | 32.0% | 13.5% |
| Constipation | 23.8% | 25.9% | 26.1% | 10.9% |
| Vomiting | 10.6% | 22.8% | 25.3% | 4.8% |
| Upper respiratory infection | 14.2% | 12.2% | 13.1% | 11.6% |
| Dysesthesia | 5.1% | 12.3% | 12.5% | 0.9% |
| Urinary tract infection | 7.5% | 8.8% | 8.4% | 5.3% |
| Discontinuation due to adverse events | 4.1% | 6.9% | 11.3% | 4.9% |
Source: Eli Lilly topline release, May 21, 2026. All figures are sponsor-reported. Peer-reviewed publication pending.
Three things stand out in this table. First, gastrointestinal events are dose-dependent. Nausea increases from 28.6% at 4 mg to 42.4% at 12 mg. Vomiting increases from 10.6% to 25.3%, about 2.4 times. Second, the placebo arm had meaningful rates of GI events too: 14.8% nausea, 13.5% diarrhea. That is not unusual in obesity trials. Third, the 11.3% discontinuation rate at 12 mg is a stop-treatment signal that warrants close attention when the full safety dataset is published and independent reviewers can contextualize it against the efficacy results.
What is dysesthesia
Dysesthesia means an unpleasant abnormal sensation. People describe it as tingling, prickling, burning, or a feeling like something is crawling on the skin. It is not numbness and it is not pain in the usual sense. It is a distortion of sensation.
In TRIUMPH-1, dysesthesia was reported in 5.1% of the 4 mg group, 12.3% of the 9 mg group, and 12.5% of the 12 mg group, compared with 0.9% of the placebo group. The rate is clearly dose-related and is not trivial at the higher doses.
Why does it happen with retatrutide and not as prominently with single or dual agonists? No one knows yet. The phase 3 publication, when it arrives, should describe the character, duration, and reversibility of the sensation. For now, the data is limited to a single percentage in a sponsor press release. The published percentage supports asking how investigators characterized the sensation, while the full report remains pending.
Phase 2 versus phase 3: why the evidence gap matters
The phase 2 trial, published in the New England Journal of Medicine in June 2023, enrolled 338 adults for 48 weeks. It was randomized, double-blind, and placebo-controlled. It showed a least-squares mean weight reduction of 24.2% at 48 weeks for the highest dose group. It also reported adverse events that were broadly consistent with incretin-based therapies.
Phase 2 enrolled 338 participants, a sample too small to characterize rare events well. Phase 3 gives investigators a larger safety dataset.
The phase 3 trial is 2,335 people. Almost seven times larger. It ran longer. It included a pre-specified extension to 104 weeks for people with class 2 and 3 obesity. And as of July 22, 2026, none of its results have been peer-reviewed or published in a medical journal. The only public data comes from a press release.
Companies often announce topline results when trials read out. The full manuscript follows months later. But a press release is sponsor communication, not independent analysis. Every adverse-event figure in the table above carries that caveat.
What the FDA has said
On June 15, 2026, the FDA updated its drug alerts page explicitly: retatrutide is not a component of an FDA-approved drug, has not been found safe and effective for any condition, and cannot be used in compounding under federal law.
The agency has warned telehealth companies and sellers about marketing unapproved drugs including retatrutide. FDA’s public position is direct.
Why “retatrutide near me” results deserve scrutiny
Search for “retatrutide near me” and you will find clinics that claim to offer the drug. Some use phrases like “research-grade” or “for laboratory use only” while selling to individuals. Others describe it as compounded retatrutide. (Registered clinical trial sites that dispense the investigational drug through an IRB-approved protocol with informed consent are a different category and are not addressed by the concerns below.)
None of those products are FDA approved. A completed phase 3 trial does not equal FDA approval. If a clinic advertises retatrutide outside a registered trial, the product they are offering is not the investigational drug from the trial. The questions below are designed to surface what it actually is.
See our city-specific peptide clinic directories: Los Angeles, Houston, Chicago, New York. For additional guidance on evaluating clinics, see our guides on what to check at a GLP-1 clinic, semaglutide clinics, 503A compounding pharmacies and peptides, and finding a peptide doctor.
Questions to ask any clinic that advertises retatrutide
- What is the exact product identity, and what is its written FDA status? Ask for a detailed written description of what is being offered and whether the FDA has reviewed or approved it for any indication. Request documentation, not a verbal description.
- Is this offer part of a registered, actively recruiting clinical trial? If the clinic says the product is provided through a trial, ask for the NCT number from ClinicalTrials.gov and confirm that the trial lists their site as actively recruiting.
- Who is the named trial clinician? A legitimate clinical trial has a named clinician overseeing the site. If the clinic cannot name a specific licensed clinician responsible for the protocol, that is a red flag.
- What is the informed-consent and medical-records process? A registered trial requires documented informed consent and maintains medical records according to the protocol. Ask how your records will be documented, stored, and made available to you.
- How does this offer respond to the FDA’s explicit statement that retatrutide cannot be used in compounding under federal law? The FDA stated on June 15, 2026, that retatrutide cannot be compounded. Ask for the clinic’s response to that specific regulatory position.
- How are patient privacy and medical information handled? Ask what privacy practices are followed, who has access to your information, and whether data is shared with third parties.
- What adverse-event reporting process is followed? FDA-approved drugs have MedWatch reporting. Investigational drugs have trial safety monitoring. Ask how adverse events are tracked, reported, and to whom.
- Can they confirm that no retail product sale is involved? A registered clinical trial does not sell the investigational drug as a retail product. If the clinic asks for payment specifically for the investigational drug, verify the arrangement with the study contact and the trial registry before proceeding.
FAQs
Is retatrutide FDA approved?
No. As of July 22, 2026, retatrutide has not been approved by the FDA for any indication. The FDA has explicitly stated it has not been found safe and effective for any condition.
When will retatrutide be released?
No release date has been announced. Eli Lilly has not disclosed a regulatory submission timeline. A completed phase 3 trial is not a release date.
What are the most common side effects shown in phase 3?
Based on Lilly’s sponsor-reported topline release, the most common adverse events at the 12 mg dose were nausea (42.4%), diarrhea (32.0%), constipation (26.1%), vomiting (25.3%), upper respiratory infection (13.1%), dysesthesia (12.5%), and urinary tract infection (8.4%). These figures have not been peer-reviewed.
Can retatrutide be obtained from a compounding pharmacy?
No. The FDA stated on June 15, 2026, that retatrutide cannot be used in compounding under federal law. The agency has sent warning letters to compounders and outsourcing facilities that handled retatrutide.
Can I join a retatrutide clinical trial instead?
Possibly. Search ClinicalTrials.gov for actively recruiting retatrutide trials. TRIUMPH-1 (NCT05929066) is completed and no longer recruiting. Other trials in the TRIUMPH program may be recruiting. Clinical trial participation involves screening, informed consent, and protocol-defined monitoring. A registered trial does not sell the investigational drug as a retail product. If a clinic charges specifically for access to the investigational drug, verify the arrangement with the study contact and the trial registry before proceeding.
Current status
Retatrutide’s phase 3 topline results, as reported by Eli Lilly on May 21, 2026, show substantial weight loss alongside dose-dependent gastrointestinal side effects and a novel dysesthesia signal. These figures are sponsor-reported and have not been peer-reviewed. The full TRIUMPH-1 dataset, including serious adverse events, laboratory findings, and subgroup analyses, has not been published.
The FDA has stated that retatrutide is not approved, has not been found safe and effective for any condition, and cannot be compounded under federal law. The agency has taken enforcement action against entities marketing or distributing the drug. Any product sold directly to consumers as retatrutide is unapproved. Readers evaluating a clinic that advertises retatrutide should ask the eight questions listed above.
Sources
- FDA Drug Alerts and Statements. “FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss.” Updated June 15, 2026. https://www.fda.gov/drugs/drug-alerts-and-statements/fdas-concerns-unapproved-glp-1-drugs-used-weight-loss
- ClinicalTrials.gov. “A Study of Retatrutide (LY3437943) in Participants With Obesity or Overweight (TRIUMPH-1).” NCT05929066. https://clinicaltrials.gov/study/NCT05929066
- Eli Lilly and Company. “Lilly’s triple agonist, retatrutide, delivered powerful weight loss in pivotal Phase 3 obesity trial.” Press release, May 21, 2026. https://investor.lilly.com/news-releases/news-release-details/lillys-triple-agonist-retatrutide-delivered-powerful-weight-loss
- Jastreboff AM, Kaplan LM, Frias JP, et al. “Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial.” N Engl J Med 2023;389:514-526. https://www.nejm.org/doi/full/10.1056/NEJMoa2301972
- FDA MedWatch. “Voluntary reports for drugs and therapeutic biological products.” https://www.fda.gov/safety/medical-product-safety-information/medwatch-forms-fda-safety-reporting