People Are Already Taking This Unapproved New Weight-Loss Drug

The long history of underground drug use abounds with secret societies—colorful cliques of like-minded individuals surreptitiously experimenting with newfangled compounds in an effort to understand their mysteries.

Mid-19th-century France saw artists and intellectuals like Baudelaire and Dumas gathered at the Club of the Hash Eaters to partake of the powerful sticky cannabis concentrate. In the latter half of the 20th century, Dow chemist Alexander Shulgin, famous for popularizing MDMA and a range of other potent psychedelic analogues, held gatherings at his home, sampling his latest creations with a group of like-minded fellow travelers. And earlier this year, when 48-year-old Jake Terry wanted to test the effects of retatrutide, a new but not-yet-approved compound developed by the pharmaceutical giant Eli Lilly, he bought some online and took it to his friends.

Unlike Shulgin or Baudelaire’s experiments, retatrutide is not psychoactive. It’s a weight-loss injectable, like semaglutide (marketed as Wegovy) or tirzepatide (marketed as Zepbound). But the key difference with this weight-loss drug, besides the pesky matter of its legality, is that it appears to be much, much more powerful than those approved so far. On the back of phase II trials, it’s already being hailed as a game-changer.

Retatrutide works by the same means as its predecessors, by interacting with receptors that are central to the body’s metabolism, ultimately lowering people’s appetite and slowing digestion. But where semaglutide acts on one receptor (the glucagon-like peptide-1, or GLP-1, receptor), and tirzepatide on two (GLP-1 and the gastric inhibitory polypeptide, or GIP, receptors), retatrutide has been nicknamed “Triple G” for its ability to work on three hormone receptors (those for GLP-1 and GIP, as well as the glucagon, or GCG, receptor).

“These are three chemically related but distinct receptors that have their own distinct biology,” says Richard DiMarchi, professor of chemistry and chair in biomolecular sciences at Indiana University. “With the three together … you can actually make a single molecule, like a master key, that opens multiple doors as effectively as [individual] keys, and achieve superior outcomes.” DiMarchi knows these drugs well, having conducted pioneering research on this class of chemicals as far back as the late 1990s while employed at Eli Lilly as group vice president of research and development. (He left the company in 2003, in part because he felt the company didn’t then prioritize obesity treatments or see the benefit of an injectable weight-loss drug.)

Following a once-weekly subcutaneous injection of retatrutide, participants in clinical trials exhibited “a significant reduction in body weight and improvement of metabolic markers.” Data collected in a phase II trial showed that obese participants lost a mean average of 24.2 percent of their body weight over a 48-week period. Compare this to 18–20 percent over 72 weeks for tirzepatide, or 14.9 percent over 68 weeks with semaglutide (both in phase III trials). “It’s such a huge drug,” says Terry. “It’s a miracle.”

Terry first became interested in these compounds back in 2023. His daughter was diagnosed with a prolactinoma: a benign tumor of the pituitary gland that, left unchecked, can interfere with metabolism, leading to weight gain. To regulate her weight, a doctor prescribed semaglutide. But the $500-a-month bill made the drug unaffordable. Terry did some research online, and came across a website selling “research chemicals.”

Such vendors—sometimes called “grey market pharmacies”—typically trade in alternative forms of commonly used psychoactive drugs, as well human-growth hormone, anabolic steroids, and other “gear” prized among the power-lifting and body-hacking sets. Such marketplaces are also used by trans and nonbinary people to source gender-affirming hormones. These websites typically carry disclaimers clarifying that the “intended use” of these compounds is for “research purposes,” allowing their sale to wiggle through a legal loophole. “If you’re selling to a lab or academic institution that is doing research, you can do that totally lawfully,” says Jesse C. Dresser, a partner at the New Jersey-based law firm Frier Levitt, which specializes in pharmaceutical practices. “That sale would be lawful, even if theoretically, the person that purchased it used it for personal consumption.” (Dresser also notes that there is “very limited enforcement” of the rules governing this space.)

The popularity of modern weight-loss treatments, combined with their high costs and shortages of supplies, have made unofficial forms of them popular in such underground online drug bazaars. It was on such a site that Terry found some tirzepatide, and procured it for his daughter. “It works,” he recalls. “She loses the weight. She looked good at her wedding. And everything’s under control.”

His interest piqued, Terry started contacting suppliers in China, who mass-produce various active pharmaceutical ingredients, or APIs, for pharma companies, regulated and otherwise. Scanning their inventories, he noticed a listing for retatrutide. He ordered 10 vials of the drug in powder form, amounting to some 200 mg. It arrived shortly after via the post, in an unbranded bubble mailer. He prepared it and injected it, following dosing protocols from Lilly’s initial clinical trials. Within two months, he’d gone from 186 to 166 pounds.

Amazed, he wanted to share the miracle with his friends. “Hey, anybody wanna try this?” he asked some buddies during a meetup, producing several vials of retatrutide. He told them about his daughter—and his own weight loss. They were keen to try it. A month later, one of them had dropped 12 pounds. One lost 16. One even shed 28 pounds. Terry was so impressed that he moved into the grey-market pharmaceutical biz himself, ordering APIs from Chinese manufacturers, and selling them—clearly marked as “research chemicals”—through his website, Compound Sciences, based out of Utah.

Another of Terry’s friends—who is also his Compound Sciences business partner, who spoke on the condition of anonymity—claims to have dropped 30 pounds on underground retatrutide. “I was 53 with the dad-bod gut,” he explains. “This is the first time in my life I’ve actually seen my abs. And I’ve changed nothing, other than retatrutide. I don’t exercise more. I don’t do anything other than take the shot once a week.”

Terry holds fast to the line that the peptides he sells are for research purposes only. He also says he tests his imported APIs for purity through third-party labs like Finnrick and Janoshik Analytical, and provides Certificates of Analysis to verify the results. (Raphaël Mazoyer, Finnrick’s COO, cautions that customers should always verify Certificates of Analysis with the companies that issued them and check they include a batch identifier.) Compound Sciences sells 20 mg of retatrutide (branded as GLP3 RT-20) for $79.99. To use the drug themselves, purchasers would have to reconstitute the powder by combining it with bacteriostatic water and injecting with a syringe, processes that are all explained in detail across multiple social media platforms, like TikTok and YouTube. In fact, like with psychedelics and steroids, whole communities have risen up devoted to experimentation with GLP-1-type drugs.

“There was a YouTube video in my feed,” says a 23-year-old retatrutide user who asks to be identified as Diana. “It was one of those fitness podcasters. He was talking about metabolism, which is something I’ve had trouble with. And he mentioned retatrutide. I thought he was just making up a word.” Upon further investigation, Diana learned that retatrutide is very much real, and easily accessible. A new mother, Diana had developed gestational diabetes and worried that, postpartum, her appetite was out of control. She suspected her insulin function was off, as she watched her blood sugar test scores rise to prediabetic levels. But more than anything, she just wanted to see what would happen. She found a retailer online, and paid for the drug using a bank transfer.

“I’m an experimental-type person,” Diana explains. “Maybe a little impulsive. I’m also not overweight. I thought, ‘Hey, if I can do this now, why not?”

Retatrutide is prized by users like Diana not only for its considerable weight-loss potential. Users of similar drugs often struggle to maintain muscle mass, because their appetites are so reduced that taking in enough calories (and protein) becomes a challenge or tedious chore. Because of its “Triple G” action, users have reported that retatrutide is able to burn fat without the extreme appetite suppression associated with without semaglutide or tirzepatide. As DiMarchi explains, glucagon, one of the hormones that reta mimics, is thermogenic, meaning that it “stimulates energy utilization.” Because users are both eating less, and burning more, the effects are greater. This has made the drug buzzy not just among people looking to lose a few (or few dozen) pounds, but with athletes, weightlifters, and body composition obsessives.

Adrian Crook, a 50-year-old fitness YouTuber based in British Columbia, Canada, first caught wind of reta from a friend in Bangkok who hyped up the “Triple G” effect to him. Crook didn’t need to drop any weight. “I just like trying things,” he says. “I have an unhealthy obsession with pharmaceutical interventions.”

Crook also has a history of gastrointestinal problems, including a Crohn’s disease diagnosis. He didn’t really care for food. “I just have a negative association with eating,” he tells WIRED. “The pitch for reta is it just puts that stuff on autopilot … it makes your cutting, your weight-maintenance effortless. You don’t have to deal with cravings, or the feeling of desperation you get from always being hungry.”

In seven weeks, Crook lost 25 pounds. However, he eventually stopped taking retatrutide after a negative experience that he attributes to the drug’s interaction with a protein pump inhibitor he was taking to manage acid reflux—itself the result of some anabolic steroids he had taken a year earlier. “It felt like how I used to feel when I had stomach obstructions from my Crohn’s disease,” he recalls. “Nothing was moving. After a couple hours I just started throwing everything up, because nothing was going the other way. That was it. If it persisted, I’d have to go to the hospital. It was bad.”

Forty-year-old “Craig” (who asked to speak on the condition of anonymity, because he works in the medical field) found his way to retatrutide more officially: by enlisting in a clinical trial. He had actually been writing a master’s thesis on GLP-1 drugs. Despite his commitment to diet and exercise, he had found himself unable to drop weight. He was diagnosed as obese, with high cholesterol, and mild asthma. “I’ve got a kid now,” he says. “I’ve got to get healthy. I’m trying to do the best for me.”

Craig was tipped-off to a trial in his area, in which he worked up to a 12 mg dose of retatrutide, once a week, the highest dose offered in Lilly’s Phase II clinical trials. He lost 31 percent of his body weight, amounting to 75–80 pounds. A dedicated runner, he was able to shave about 90 seconds off his per-mile pace. And as an avid foodie, Craig also found that his reduced appetite allowed him to actually enjoy eating more. “Because I can’t eat as much, I have a better relationship with food,” he says. “I have more mental space to do other things instead of just thinking about, like, when I’m going to eat again.”

Such endorsements abound online. Other reta boosters also flag its alleged ability to reduce cravings for drugs and alcohol. (Some clinical literature has suggested the potential of GLP-1-type drugs in the treatment of addiction, attributable to their ability to rewire dopamine signaling in the brain.) Less desirable side effects reported, in trials and anecdotally, include low energy, dizziness, cutaneous hyperesthesia (a form of extreme sensitivity to touch), and decreased libido.

Eli Lilly, the drug’s aboveboard manufacturer, is currently completing Phase III trials. If all goes according to plan, FDA approval should follow, and marketability by late 2026 or early 2027 could be possible, based on the timelines of other drugs in the category. In a statement to WIRED, a Lilly spokesperson Niki Biro noted that, given its effectiveness, retatrutide is currently being targeted to “those with high BMI or with obesity-related complications that require a high degree of weight loss, where the clinical need may be greater.”

Biro also cautions that “retatrutide is an investigational molecule that is legally available only to participants in Lilly’s clinical trials. Anyone purporting to sell retatrutide for human use is breaking the law, and no one should consider taking anything claiming to be retatrutide outside of a Lilly-sponsored clinical trial.” When WIRED put this to Terry, he reiterated that the products are not intended for human consumption. “It’s for research purposes only,” he says. “It’s all over the website.”

Suffice to say, online retailers potentially risk infringing on patents protected by pharmaceutical companies. Indeed, Dresser says producers of such chemicals can glean the drug’s molecular structure by referring to patent literature submitted by pharmaceutical sponsors to regulatory agencies like the FDA.

When reached for comment, the FDA pointed to past warnings issued against companies selling retatrutide. “These products have been sold directly to consumers for human use with dosing instructions,” the FDA’s statement to WIRED read. “The agency urges consumers not to purchase these products, which are of unknown quality and may be harmful to their health.”

Until FDA approval, the drug is likely to find a thriving market online, investigated by users looking to kick-start weight loss or speed up their cuts, and purveyed by middle-man retailers like Jake Terry. “The only reason I’ve done this is to make it more accessible,” Terry says. “If I can help people become more healthy, that’s my goal.”