Retatrutide Reviews: Pros, Cons and Complaints, Checked Against the Trials
Retatrutide reviews, checked: what 7,720 people in 6 Phase 3 trials lost, why some quit, and what online reta reviews can't tell you about a vial.
The best retatrutide reviews are the Phase 3 trials, and they come out strong on weight loss and mixed on comfort. In Lilly's 6 reported Phase 3 trials, people on the top 12 mg dose lost 16.8% to 28.7% of their body weight on average, and 5.1% to 18.2% of them stopped because of side effects, with stomach trouble at the top of every trial's list. In the one trial against another drug, 12 mg took off 20.9% of body weight against 9.4% on Ozempic 2 mg. Since no approved version exists yet, anyone reviewing retatrutide outside a trial is using a vial no regulator has checked.
Key takeaways
- Across 6 Phase 3 trials, people on 12 mg lost 16.8% to 28.7% on average, and the three lowest averages came from the trials in people with type 2 diabetes.
- The share who quit over side effects on 12 mg ran from 5.1% to 18.2%, against 0.0% to 4.9% on placebo and 2.7% on Ozempic in the one trial without a placebo.
- On 4 mg in TRIUMPH-1, fewer people quit over side effects than on placebo, and they still lost 19.0% on average.
- In a JAMA Network Open study of Reddit posts from 7,823 people using unapproved retatrutide, increased appetite (17.1%) came up more often than nausea (11.6%).
- Most online reta reviews are about vials from peptide sellers, and one that Australia's regulator tested held semaglutide instead of retatrutide.
A post on a forum is one person, one vial and one bathroom scale. A Phase 3 trial is hundreds or thousands of people with a comparison group, all using a product that was checked before anyone injected it. Below, the two sit side by side.
Retatrutide reviews from 7,720 trial participants
Lilly reported 6 Phase 3 trials between December 2025 and October 2026, and 7,720 people were randomized across them, adding up Lilly's figures for each trial. The table uses 12 mg, the top dose in every trial (retatrutide weight loss has every dose and time point), and for weight, Lilly's efficacy estimand, which counts results as if everyone had stayed on the drug. The comparison group got placebo in every trial except TRANSCEND-T2D-2, where it got Ozempic 2 mg.
| Trial and who took part | People | Weeks | Weight lost, 12 mg vs comparator | Nausea, 12 mg vs comparator | Stopped for side effects, 12 mg vs comparator |
|---|---|---|---|---|---|
| TRIUMPH-4: obesity with knee osteoarthritis | 445 | 68 | 28.7% vs 2.1% | 43.2% vs 10.7% | 18.2% vs 4.0% |
| TRIUMPH-1: obesity or overweight, no diabetes | 2,339 | 80 | 28.3% vs 2.2% | 42.4% vs 14.8% | 11.3% vs 4.9% |
| TRIUMPH-3: severe obesity with heart disease | 1,949 | 80 | 22.6% vs 3.2% | 22.4% vs 5.8% | 13.5% vs 4.8% |
| TRANSCEND-T2D-2: type 2 diabetes, vs Ozempic 2 mg | 1,298 | 80 | 20.9% vs 9.4% | 23.8% vs 21.3% | 7.9% vs 2.7% |
| TRIUMPH-2: obesity with type 2 diabetes | 1,152 | 80 | 20.8% vs 4.0% | 28.0% vs 8.0% | 7.7% vs 4.9% |
| TRANSCEND-T2D-1: type 2 diabetes | 537 | 40 | 16.8% vs 2.5% | 26.5% vs 3.7% | 5.1% vs 0.0% |
Sources: Lilly's topline releases for TRIUMPH-4 (December 11, 2025), TRANSCEND-T2D-1 (March 19, 2026), TRIUMPH-1 (May 21, 2026), TRIUMPH-2 and TRIUMPH-3 (July 23, 2026), and TRANSCEND-T2D-2 (October 28, 2026).
People with type 2 diabetes lost less. The three lowest averages, 20.9%, 20.8% and 16.8%, all come from diabetes trials, and TRANSCEND-T2D-1 ran for 40 weeks, half as long as the 80-week trials. The quit rate moved around more than the weight loss did. TRIUMPH-4 had the highest, and Lilly said stopping there tracked with starting BMI and included people who quit because they felt they'd lost too much weight.
TRANSCEND-T2D-2 is the first time retatrutide was tested against another incretin drug. Nausea on 12 mg was close to Ozempic's (23.8% vs 21.3%), and so was vomiting (15.0% vs 13.2%). Quitting wasn't. About 3 times as many people stopped 12 mg over side effects as stopped Ozempic, 7.9% against 2.7%, so more weight loss came with more people stopping. The trial was open label, so everyone knew which drug they were on, and there's no journal paper yet. Our retatrutide clinical trials page has the details.
Pros and cons of retatrutide
| Pros, from trial data | Cons, from trial data and gaps |
|---|---|
| 45.3% of people on 12 mg lost 30% or more of their weight in TRIUMPH-1 | Nausea hit about 4 in 10 people on 12 mg (42.4%) in TRIUMPH-1 |
| 12 mg took off 20.9% of body weight vs 9.4% on Ozempic 2 mg in TRANSCEND-T2D-2 | 7.9% quit 12 mg over side effects vs 2.7% on Ozempic in the same trial |
| Triglycerides fell by up to 41.0% and systolic blood pressure by up to 12.3 mmHg in TRIUMPH-1 | Burning or oversensitive skin (dysesthesia) in 12.5% on 12 mg vs 0.9% on placebo in TRIUMPH-1 |
| Knee pain scores fell 75.8% on 9 mg in TRIUMPH-4 (a post hoc figure) | Heart rate rose with dose in the Phase 2 trial, peaking at 24 weeks before easing |
| Breathing pauses in sleep fell by 34.3 an hour on 9 mg vs 9.9 on placebo in TRIUMPH-1's sleep apnea trial (NEJM, hybrid-treatment estimand) | No approved version, price or launch date as of October 2026 |
| On 4 mg in TRIUMPH-1, 4.1% quit over side effects (4.9% on placebo) and people still lost 19.0% | No Phase 3 results yet on what happens to weight after stopping retatrutide |
The cons column may still grow, because Lilly's releases leave out some safety data. As of October 31, 2026, three of the six trials have a peer-reviewed paper: TRIUMPH-1 in NEJM, and TRIUMPH-2 and TRANSCEND-T2D-1 in The Lancet. TRIUMPH-3, TRIUMPH-4 and TRANSCEND-T2D-2 have only Lilly's releases, and no release or journal abstract gives a serious adverse event rate. The NEJM paper also leads with a lower number for 12 mg than Lilly's 28.3%: 25.0% against 3.9% on placebo, because it counts everyone randomized, including people who stopped.
The heart question is open too. TRIUMPH-3 counted 27 major heart events (MACE-3) on retatrutide and 23 on placebo (hazard ratio 1.12, 95% confidence interval 0.64 to 1.96), too few to say anything either way. TRIUMPH-Outcomes, built to answer it, has an estimated primary completion of February 2029 on ClinicalTrials.gov.
Retatrutide reviews and complaints from people using it
These are user reports, not studies. On r/Retatrutide, thread titles ask about sunburn-like skin, waking at 2:30 am, a higher resting heart rate, and how long weight loss takes to start after switching from tirzepatide. One poster who moved over from tirzepatide wrote three weeks in that they weren't getting the hunger-blunting effect. No retatrutide trial has published results on switching; switching from tirzepatide covers what is and isn't known.
The biggest count of these reports so far is a JAMA Network Open study published in October 2026. Its authors ran 148,640 retatrutide posts and comments from Reddit through a language-model classifier and analyzed 7,823 users who described taking unapproved retatrutide. The effects they mentioned most were increased appetite (17.1%), fatigue (15.2%), more energy (12.4%), nausea (11.6%), food cravings (7.3%) and insomnia (6.1%). Nobody checked what was in anyone's vial.
Our read: increased appetite topping that list is odd, since trial participants reported the opposite (decreased appetite in 18.2% on 12 mg in TRIUMPH-4). A vial with little or no retatrutide would fit, and so would posts written as a dose wears off; the study can't separate the two.
In TRIUMPH-1, Lilly counted side effects against placebo.
Side effects on 12 mg vs placebo in TRIUMPH-1
Share of people who reported each effect at least once over 80 weeks
The skin symptom shows up beyond TRIUMPH-1 too: on 12 mg it reached 20.9% in TRIUMPH-4 (0.7% on placebo) and 6.5% in TRANSCEND-T2D-2 (2.7% on Ozempic). Sleep is the opposite case. Plenty of r/Retatrutide threads ask about it, yet no trial release or journal abstract gives an insomnia rate; retatrutide insomnia covers what's known. For a symptom-by-symptom breakdown, see retatrutide side effects; for what the threads themselves are about, see retatrutide on Reddit.
When to get medical help
Get same-day care for belly pain that is severe or won't go away, vomiting or diarrhea that stops you keeping fluids down, yellow skin or eyes, dark urine, unusual bruising, swelling of the face or throat, or trouble breathing. If you take insulin or a sulfonylurea, shakiness, sweating and confusion can mean low blood sugar.Why online reta reviews and trial results don't match
The first reason is who posts. Someone who lost 80 pounds uploads photos; someone who quit after three weeks of vomiting often doesn't post at all. Trials keep count of everyone who started, including the people who stopped, which is why the table above has a column that online reviews don't.
The second reason is the vial. Every trial result on this page comes from Lilly's own tested product. In a safety advisory published September 14, 2026, Australia's TGA said a person had uncontrollable vomiting and a torn esophagus after using a product sold as retatrutide. Its lab found no retatrutide in the vial, and semaglutide at about 8 times the level in approved products. In June 2026, Victoria's health department linked 6 cases of acute liver injury since January to unapproved products labeled retatrutide, possibly from a contaminant.
Dose is the third. Online reviewers mix powder with their own water and read doses off insulin syringes, so "2 mg" in one review and "2 mg" in another may not match. Lilly's releases, most recently on October 28, 2026, say retatrutide "cannot be legally sold or marketed for human use"; is retatrutide legal covers what that means country by country. If you're reading reviews on a page offering retatrutide for sale, the reviews can vouch for shipping and service; only a batch-specific lab report tells you what's in the vial.
How to read a reta peptide review
The US Federal Trade Commission's rule on fake reviews, announced August 14, 2024, bans buying or selling fake reviews, paying for reviews that express a set opinion, and passing off a company-run site as an independent review site. It can't tell you whether a given page follows it, so check the review itself:
- Look for the dose, the time on it and the starting weight. A review without all three can't be compared with any trial.
- Check for other drugs in the post history, such as tirzepatide, testosterone or stimulants. They change both the scale and the photos.
- Ask whether the reviewer saw a lab report for their batch, covering identity, purity, amount per vial and endotoxin, with a batch number that matches the vial.
- Treat claims of approval, "pharmaceutical grade", Lilly branding or pens as red flags. Lilly's October 28, 2026 release says: "Anyone purporting to sell retatrutide to consumers is breaking the law."
- Compare the result with the trial average for the same dose and time frame, not with the most upvoted post of the year.
For photos, retatrutide before and after sets Reddit photos against the trial numbers.
GLP-3 drops and other GLP three products
GLP-3 is a nickname. Lilly's FAQ calls it a scientifically inaccurate label; our GLP-3 page explains where the name came from. Sellers use it anyway: an FDA warning letter dated August 24, 2026 named a product called "GLP-3 Reta (Retatrutide)" as an unapproved new drug.
Drops sold under a "GLP three" name are another matter. Lilly's FAQ says retatrutide is given as a once-weekly injection under the skin in its trials, so a review of drops says nothing about retatrutide. Read the ingredient list first: if retatrutide isn't on it, the review is about a different product. Our oral retatrutide page covers the pills, drops and sprays sold as reta.
Is retatrutide worth it?
On the evidence so far, retatrutide delivers big average weight losses, and many people pay for them with stomach trouble. Here's what the TRIUMPH-1 averages would mean for someone starting at 220 pounds, over 80 weeks (our arithmetic from Lilly's percentages):
| TRIUMPH-1 dose | Average loss | At a 220 lb start | Stopped for side effects |
|---|---|---|---|
| 4 mg | 19.0% | about 42 lb | 4.1% |
| 9 mg | 25.9% | about 57 lb | 6.9% |
| 12 mg | 28.3% | about 62 lb | 11.3% |
| Placebo | 2.2% | about 5 lb | 4.9% |
Averages hide a wide range. Move the slider to see the 12 mg average at your weight; the full retatrutide weight loss calculator has the other trials, and the weight loss timeline shows how fast the weight came off.
What the trial average would mean at your start weight
Based on the 12 mg, 80 weeks (TRIUMPH-1) average of 28.3%. A trial average, not a prediction for any one person. Results vary with dose, adherence and starting weight.
Open the weight-loss calculatorOur read: the numbers make retatrutide look worth waiting for, and nothing in them applies to a vial bought online. The one comparison most reviewers want, against tirzepatide, is TRIUMPH-5; its estimated primary completion is November 2026, and there are no results as of October 31, 2026. Until then, retatrutide vs tirzepatide compares the two across separate trials.
On timing, Lilly last said, on September 29, 2026, that it plans to submit retatrutide to the FDA in the first quarter of 2027 as a Biologics License Application (BLA). On October 2, 2026, the FDA decided that retatrutide is a drug, not a biological product, so an application would need to be filed under section 505 of the Federal Food, Drug, and Cosmetic Act. Lilly's appeal on that question is pending in the Seventh Circuit, and we found no ruling as of October 31, 2026. Our release date page tracks it.
The legitimate routes as of October 2026 are a clinical trial, Lilly's narrow expanded access program, or an approved drug; how to get retatrutide walks through each. For approved options, Zepbound self-pay on LillyDirect runs $299 to $449 a month (the top price needs a refill within 45 days), and Wegovy pens cost $349 a month through NovoCare after the introductory fills. Lilly hasn't announced a retatrutide price; retatrutide price covers what is and isn't known.
If a product sold as retatrutide made you ill, get care first, then report it to the FDA through MedWatch; Lilly also asks people to report illegal retatrutide products to 1-800-LillyRx.
Frequently asked questions
Is retatrutide worth it?
On the trial numbers it works well: 28.3% average loss on 12 mg over 80 weeks in TRIUMPH-1, and more than twice Ozempic's weight loss in the one head-to-head trial. The price is stomach side effects for many people and a quit rate of up to 18.2% on 12 mg. It isn't approved or sold legally anywhere yet, so for now the choice is a clinical trial or an approved drug.
Is it worth taking retatrutide before it's approved?
Lilly says retatrutide cannot be legally sold or marketed for human use, so anything sold online isn't Lilly's product. Australia's TGA tested one vial sold as retatrutide and found semaglutide at about 8 times the level in approved semaglutide products, and Victoria's health department reported 6 cases of liver injury in people who used products labeled retatrutide. The trial results only apply to Lilly's tested product.
What are the most common retatrutide complaints?
Nausea, diarrhea, constipation and vomiting top the trial lists. In TRIUMPH-1, nausea affected 42.4% of people on 12 mg against 14.8% on placebo. On Reddit, a JAMA Network Open study found increased appetite, fatigue and more energy mentioned most, with nausea fourth, and people also complain about burning skin, poor sleep and a faster heart rate; of those three, only the skin symptom has a published trial rate.
Are GLP-3 drops the same as retatrutide?
No. GLP-3 is a nickname for retatrutide, which Lilly calls scientifically inaccurate. Lilly's trials give retatrutide as a once-weekly injection under the skin, so every published result comes from a shot. A review of drops tells you nothing about retatrutide as tested.
Are there real patient reviews of retatrutide?
The closest thing is trial data: 7,720 people randomized across Lilly's 6 reported Phase 3 trials, with placebo or Ozempic groups and counted dropouts. Reviews on Reddit, YouTube and seller sites are real people's reports, but almost all involve unapproved vials whose contents no regulator checked. Read them as stories, not as evidence.
Sources
- Lilly's triple agonist, retatrutide, delivered weight loss of up to an average of 71.2 lbs along with substantial relief from osteoarthritis pain in first successful Phase 3 trial (TRIUMPH-4 topline). Eli Lilly and Company (PR Newswire), 2025. prnewswire.com
- Lilly's triple agonist, retatrutide, delivered powerful weight loss in pivotal Phase 3 obesity trial (TRIUMPH-1 topline). Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- Lilly's triple agonist, retatrutide, successful in two additional Phase 3 obesity trials, delivering significant improvements in weight and A1C (TRIUMPH-2 and TRIUMPH-3 topline). Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- Lilly's triple agonist, retatrutide, demonstrated significant reductions in A1C and weight in first Phase 3 trial for treatment of type 2 diabetes (TRANSCEND-T2D-1 topline). Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- Lilly's retatrutide delivered greater A1C reduction and more than double the weight loss of Ozempic's highest approved dose in head-to-head trial (TRANSCEND-T2D-2 topline). Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- Lilly's triple agonist, retatrutide, drove substantial improvements in weight, A1C, knee osteoarthritis pain, and obstructive sleep apnea (TRIUMPH-1 and TRANSCEND-T2D-1 at ADA 2026). Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- Triple-Hormone-Receptor Agonist Retatrutide for Obesity: A Phase 2 Trial. The New England Journal of Medicine, 2023. doi.org
- Retatrutide Once Weekly for Treatment of Obstructive Sleep Apnea (TRIUMPH-1-OSA and TRIUMPH-2-OSA; Grunstein RR et al.). The New England Journal of Medicine, 2026. doi.org
- Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity (TRIUMPH-1; Jastreboff AM et al.). The New England Journal of Medicine, 2026. doi.org
- Bellido V et al., TRIUMPH-2 trial report, Lancet 2026;408(10563):1455-1472. The Lancet, 2026. doi.org
- Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial. The Lancet, 2026. doi.org
- The Effect of Retatrutide Once Weekly on Cardiovascular Outcomes and Kidney Outcomes in Adults Living With Obesity (TRIUMPH-Outcomes, NCT06383390). ClinicalTrials.gov, 2026. clinicaltrials.gov
- Lilly's triple agonist, retatrutide, delivered substantial weight loss and A1C reduction, underscoring its potential promise for people with obesity and type 2 diabetes. Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- Cross-sectional study of Reddit posts on non-approved retatrutide use (Sehgal NKR et al., JAMA Netw Open 2026;9(10):e2638929). JAMA Network Open, 2026. doi.org
- TGA tests counterfeit retatrutide product following serious adverse event report. Therapeutic Goods Administration (Australia), 2026. tga.gov.au
- Toxicity linked to unapproved peptide retatrutide. Department of Health, Victoria, 2026. health.vic.gov.au
- Federal Trade Commission Announces Final Rule Banning Fake Reviews and Testimonials. U.S. Federal Trade Commission, 2024. ftc.gov
- What to know about retatrutide. Eli Lilly and Company, 2026. lilly.com
- Warning letter: Peptide Partners LLC (MARCS-CMS 735063). U.S. Food and Drug Administration, 2026. fda.gov
- A Study of Retatrutide (LY3437943) Compared to Tirzepatide (LY3298176) in Adults Who Have Obesity (TRIUMPH-5, NCT06662383). ClinicalTrials.gov, 2026. clinicaltrials.gov
- FDA letter of October 2, 2026 on remand: retatrutide is not a biological product (Eli Lilly and Company v. Kennedy, 7th Cir. No. 26-1301, Doc. 46-2). U.S. Food and Drug Administration, via CourtListener, 2026. storage.courtlistener.com
- Eli Lilly and Company v. Robert Kennedy Jr., 7th Cir. No. 26-1301 (docket). CourtListener, 2026. courtlistener.com
- Pre-approval Expanded Access of Retatrutide (LY3437943), NCT07629401. ClinicalTrials.gov, 2026. clinicaltrials.gov
- Zepbound self-pay pricing on LillyDirect. Eli Lilly and Company, 2026. lilly.com
- NovoCare Pharmacy: Wegovy self-pay pricing. Novo Nordisk, 2026. novocare.com
- Lilly calls on online platforms, payment companies and regulators to shut down the illegal retatrutide black market. Eli Lilly and Company (PR Newswire), 2026. prnewswire.com
- MedWatch: The FDA Safety Information and Adverse Event Reporting Program. U.S. Food and Drug Administration, 2026. fda.gov
Dr. Juan Pablo Frías, MD
Physician-Scientist & Clinical Trialist • Endocrinology, Diabetes & Metabolism
Dr. Frías earned his M.D. from Vanderbilt University School of Medicine and completed his endocrinology fellowship at UC San Diego. A principal investigator on landmark incretin trials (including retatrutide, tirzepatide and semaglutide), he reviews all guides on Retatrutide360 for clinical accuracy, dosing safety and evidence fidelity.
Related guides & clinical tools
Continue reading our evidence-backed guides and use our syringe calculation tools.
Retatrutide Weight Loss Results
Retatrutide weight loss averaged up to 28.3% in TRIUMPH-1, and 20.9% vs 9.4% on Ozempic head to head. Every trial by dose, who lost less, what averages hide.
Retatrutide Reddit
Retatrutide Reddit, sorted: we grouped 768 thread titles by topic and checked the dosing, results and side effect claims against Lilly's Phase 3 trial data.
Retatrutide Side Effects
Retatrutide side effects by dose from six Phase 3 trials: nausea in up to 43.2%, skin sensitivity, how it compares with Ozempic, rare risks and what helps.
Retatrutide Before and After
Retatrutide before and after, measured: 17.5% lost by week 24 and 28.3% by week 80 on 12 mg in trials. See how Reddit photos compare and how to track yours.
Retatrutide Weight Loss Calculator
Retatrutide weight loss calculator: turn Phase 2 and 3 trial averages into pounds or kilograms at your start weight, with caveats for diabetes and dropouts.
Turn any dose into syringe units
Vial, water and dose in, exact syringe units out. Calculates reconstitution volumes and needle tick marks for 5 mg to 60 mg vials with zero guesswork.