A new weight loss injection called retatrutide has shown remarkable results in helping users shed weight quickly.
However, recent research suggests that the drug, which is developed by the makers of Mounjaro, may come with concerning side effects, including bone fractures and kidney issues.
Early trials of retatrutide revealed that users could lose up to a quarter of their body weight in under a year, making it nearly twice as effective as Ozempic.
Unlike other weight loss jabs, this drug not only reduces appetite but also speeds up metabolism, intensifying fat loss.
Yet, some participants in clinical trials reported losing too much weight too rapidly. One individual dropped 22% of their body weight in just nine months and felt compelled to skip doses to slow down the effects.
Another lost nearly a third of their body weight in eight months and developed kidney stones, a potentially dangerous condition.
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On social media, some users claim to have accessed retatrutide before official approval in the US or UK. Many boast about losing over three stone in just a few months.
Dubbed ‘triple g,’ the once-weekly injection targets three key hormones that influence appetite and metabolism, making it more potent than Ozempic, which targets one, and Mounjaro, which targets two.
While it remains uncertain whether the kidney stone case was directly caused by the rapid weight loss, studies suggest that GLP-1 agonists—the class of drugs retatrutide belongs to—could contribute to such risks.
Another trial participant who lost 31% of their body weight had to adjust their diet, incorporating calorie-dense foods like peanut butter to avoid further weight loss.
One participant said: “I go to my visits and they’re like, make sure you eat as much as you can. It’s odd to be in an obesity trial and try not to lose any more weight.”
Due to confidentiality agreements, the identities of the trial participants remain undisclosed. Eli Lilly, the pharmaceutical company behind retatrutide, declined to comment on the protocols of its ongoing trials but stated that patient safety is a priority.
“We actively engage in monitoring, evaluating, and reporting safety information for all our medicines,” the company said.
Experts have long warned about the risks associated with extreme and rapid weight loss. Side effects can include pancreatitis (inflammation of the pancreas), gallstones, loss of muscle mass, and weakened bones.
Dr John Batsis, an associate professor of medicine at the University of North Carolina, noted that some of his patients who used similar weight loss treatments became frail and even suffered fractures.
He said: “How much is too much weight loss is unknown, and we really need additional data and need studies to look at that.
“We need to be mindful of how much to push. Just because we can, doesn’t mean we should.”
Concerns about weight loss drugs have been raised before. Last month, singer Avery revealed she had developed osteoporosis after losing excessive weight on Ozempic.
The 30-year-old from Phoenix, Arizona, who had struggled with an eating disorder, admitted: “I thought I needed Ozempic to be beautiful and successful.”
In phase two trials involving 338 obese participants, women on retatrutide lost an average of 28.5% of their body weight over 48 weeks, while men lost an average of 21.2%.
More obese participants saw an even greater percentage of weight loss, averaging 26.5% over the same period. Unusually, 100% of trial participants lost at least 5% of their weight.
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Despite its effectiveness, retatrutide comes with common side effects, such as nausea, diarrhoea, and constipation.
However, the study, published in the New England Journal of Medicine, also highlighted its potential benefits beyond weight loss.
Participants experienced improvements in blood pressure and blood sugar levels, with four in ten being able to stop taking medication for high blood pressure.
Compared to retatrutide’s results, previous trials for Ozempic showed a 15% weight reduction over 68 weeks, while Mounjaro helped users shed up to 22.5% of their body weight over 72 weeks.
On TikTok, users continue to praise retatrutide, calling it a “gamechanger.” One user claimed: “I haven’t had any hunger cravings, my energy levels have been through the roof, and it’s been extremely easy to stick to my diet. I highly recommend it.”
Another shared their progress: “Started at 264 lbs, now 239 lbs. 25 lbs down in six weeks. Love the way I feel on Reta.”
However, the high demand for the drug has led to an underground market where individuals seek out unregulated sources.
On forums like Reddit and Telegram, users discuss ways to buy the jab in bulk and verify its authenticity.
“I always order from heavily tested sources with long reputations, even if they’re more expensive,” one person shared.
Others discuss buying from labs that disguise shipments as skincare products to bypass restrictions.
Reports have also surfaced about counterfeit versions of retatrutide being sold in Britain for as little as £2 per dose.
Some of these products come from Chinese labs and are labelled as “research only” to evade legal scrutiny.
As excitement around the drug continues to grow, researchers and medical experts stress the importance of ongoing studies to ensure its safety and long-term effects.
