Doctors are raising alarms over the widespread use of an unapproved weight-loss drug, dubbed retatrutide or 'Reta,' describing the situation as a "huge, unregulated human experiment." The drug, which targets appetite suppression like Mounjaro and Ozempic, is still in clinical trials and has not received approval from health officials.
The soaring demand for weight-loss injections has fueled a black market for retatrutide, with investigations revealing its sale online by influencers, spas, and beauty clinics under codenames to evade detection. While clinical trials suggest retatrutide can lead to significant weight loss—up to a third of body weight in less than a year—experts warn that individuals obtaining it from unlicensed sellers risk receiving fake, contaminated, or improperly dosed substances.
Health Risks and Liver Damage Reports
Serious health concerns have emerged, including reports from Australia where six individuals were hospitalized with severe liver damage after taking unlicensed doses of retatrutide. Megan Hancocks, 32, shared her experience of being hospitalized with acute liver failure after using a peptide sourced from a Chinese manufacturer, bought during a beauty appointment. Her symptoms included jaundice, nausea, vomiting, extreme fatigue, and severe constipation.
Courtney Younglove, founder and medical director of Heartland Weight Loss in Kansas, stated that without knowing the best candidates, optimal doses, titration methods, and adverse effects, current users are part of an uncontrolled experiment. Anne Peters, a professor of clinical medicine at the Keck School of Medicine, noted the unprecedented demand for a drug not yet approved by the Food and Drug Administration (FDA), contrasting it with demand for supplements rather than investigational drugs.
Drug Mechanism and Trial Results
Retatrutide, manufactured by Eli Lilly, targets the glucagon-like peptide-1 (GLP-1) hormone, similar to existing weight-loss drugs. However, it also acts on two other hormones, GIP and glucagon, earning it the designation 'GLP-3.' Clinical trials have shown impressive weight loss results, with patients on a 12mg dose losing an average of 28.3% of their body weight over 18 months. Nearly half of study participants achieved over 30% weight loss, a level comparable to bariatric surgery outcomes. In comparison, the currently approved Mounjaro leads to about 20.9% weight loss over 72 weeks.
While retatrutide, like other GLP-1 drugs, can cause gastrointestinal side effects such as nausea, vomiting, diarrhea, and constipation, the unlicensed use raises concerns about more severe issues. A study analyzing Reddit posts from over 13,000 users indicated reports of fatigue, increased energy, food cravings, and elevated heart rate, leading experts to question the authenticity of some obtained products.
Black Market Concerns and Regulatory Scrutiny
Hundreds of thousands of retatrutide doses may have entered the U.S. in the first four months of the year, with fears that significant quantities are flooding the black market. Timothy Macket, a professor at the University of California San Diego specializing in fake medications, highlighted the substantial demand and numerous avenues for illicit acquisition. Eli Lilly has warned that black market retatrutide might be counterfeit and lack any active drug.
The FDA has received approximately 40 reports of suspected adverse reactions linked to retatrutide, including heart problems, appendicitis, and blurred vision, with 14 hospitalizations and four life-threatening cases.
Despite the risks, some users are reportedly willing to gamble on the drug for rapid weight loss. Jacob Hanzel, 31, who purchases what he believes is retatrutide through a WhatsApp group, has it tested at a lab and undergoes regular health checks. Research indicates that men aged 25 to 34 are the most likely to purchase the drug illegally, a trend experts attribute to its popularity among gym-goers, likening it to the pattern seen with steroids. Dr. Luke Turnock, a performance-enhancing expert at the University of Lincoln, cautioned that as an experimental medicine, retatrutide may have unknown long-term risks, and illicit market products carry inherent uncertainties regarding purity and dosage.