Tom accidentally took eight times the recommended dose of counterfeit retatropeptide and says he nearly ended up in the hospital.
Researchers often feel excited when a new drug is developed, especially one that shows promising results in early clinical trials.
But the new weight-loss drug, retatropeptide, has created problems not only for its parent company, Eli Lilly, but also for regulators in the UK and around the world.
Experts told the BBC that this is the first time they have seen such widespread distribution of generic versions of experimental drugs still in the testing stage.
In the UK, small vials purportedly containing “reta” (cannabis extract) are being sold in gyms, nail salons, hairdressers, social media and even by street flower vendors.
”The world has gone crazy,” said Sehar Shahid, a pharmacist and director of a 24-hour pharmacy. “People are actually injecting drugs, but they think it’s safe.”
”It’s become a very common phenomenon now. People openly discuss their drug dealers, where to buy the best drugs, and post this information all over social media.”
A quick glance at my social media pages is enough to order a batch of a drug called retatrutide in minutes – although I cannot confirm its actual composition, action, or source.
Inspired by this, users are posting before and after photos on TikTok, describing how it eliminates the sound of eating, helps them lose weight, and some even say it has completely changed their lives.
The question is: despite the positive results of recent clinical trials, the safety and efficacy of retatroptide are still being tested.
In the United States, only 50% of drugs in Phase III clinical trials ultimately receive approval from the Food and Drug Administration (FDA), leaving retatreptide’s market entry uncertain. The high failure rate is primarily due to the drug’s lower efficacy in large, diverse populations compared to earlier, smaller trials, or the identification of unexpected safety risks.
Counterfeit products currently sold on the market may not match products developed in safe laboratory conditions.
Last year, the UK’s medicines regulator raided an illegal weight-loss drug factory in Northampton and seized more than 2,000 unlicensed retatropeptide injection pens.
Eli Lilly’s website contains a stern warning: “No one should take any product that claims to contain retartrutide outside of an Eli Lilly-sponsored clinical trial.”
”Illegal retatritide-based products may contain unknown ingredients, harmful contaminants, and impurities. These products may also contain excessively high or low levels of active ingredients, or contain completely unsuitable ingredients.”
”Some young, healthy patients have been hospitalised with nausea, vomiting and diarrhoea, and in some cases they have even developed kidney failure,” said Professor Donald O’Shea, an endocrinologist.
He said some personal trainers not only provide the drug to their clients, but also inject it into them.
Tom says it’s not for weight loss—he works out almost every day—but to curb his sweet tooth.
Tom Davis said he nearly ended up in the hospital after mistakenly overdosing on counterfeit retatropeptide. He ordered it from a Chinese supplier on the recommendation of a friend at the gym.
”It was terrifying,” said the 20-year-old from Brighton. “I felt a lot of pressure on my body, and my stomach was so bloated it felt like someone was putting 20 kilograms of weight on it.”
”I had diarrhea and nausea for a full 72 hours. I thought if this continued, I’d end up in the emergency room.”
Tom later realized he had taken eight times the recommended dose. Depending on the prescription, generic retatroptide may need to be mixed with sterile antibacterial water, which requires different calculations.
Dr Nas Khatak, from Chester, a medical researcher who examined patients for trials of weight-loss drugs, said those who provided counterfeit drugs were essentially guinea pigs, without any medical supervision.
He said trial participants must meet strict criteria before they are allowed to start taking the drug itself or a placebo.
”We’ll request their physician’s medical records to ensure their emotional well-being. We’ll assess their suicidal tendencies, self-harm, and mental health—all of which are done by physicians.”
”Then we’ll come back to check the blood test results, review all the information and decide if they’re suitable.”
Tom decided to look deeper into the dosage issue and, despite previously experiencing serious side effects, decided to try the generic version of retatroptide he had been taking. After nine months of cyclical use, he reported that his cravings for sweets and unhealthy foods had disappeared.
Pharmacist Shahid warned that just because counterfeit Ritalin works for one person doesn’t mean it will work for another.
Currently available weight loss drugs, such as smeglutide (brand name: Wegovy) and telapatetide (brand name: Mounjaro), act on only one or two hormone receptors. However, if approved, retatroptide would be the world’s first weight loss drug that targets three hormone receptors, hence its nickname “Triple G.”
GLP-1 slows stomach emptying, sends satiety signals to the brain that reduce appetite, and helps control blood sugar levels.
GIP – It may enhance insulin secretion, improve insulin sensitivity, and act synergistically with GLP-1 to help the body absorb nutrients and reduce hunger.
Glucagon, a hormone unique to retatropeptide, increases resting energy expenditure, causing the body to burn more calories, promotes the breakdown of fat in the liver, and aids in weight loss.
Lisa King has been taking counterfeit retatrutide since July, and at one point she was losing 3 kilograms a week by going to the gym and eating a healthy diet.
She also believes that GLP-1 inhibitors may help control some symptoms of ovarian polyendocrine metabolic syndrome (PMS). GLP-1 inhibitors help regulate blood sugar levels, and some studies have shown that these weight-loss medications may help alleviate some of the problems associated with PMS, such as extreme fatigue, kidney problems, and high blood pressure.
”I’m not sure if it’s related to the retinopathy,” Lisa said, “but my sweet cravings have decreased, my periods have become more regular, and I have a lot more energy.”
Other users who took counterfeit Retatritide reported a range of problems, including brain fog, nausea, diarrhea, decreased libido, and an inability to experience pleasure or joy.
Doctors are increasingly concerned about the side effects experienced by users of these counterfeit weight loss drugs.
Dr Sahira Dahl, a GP and president of the British Association of Islamic Medicine, said healthcare professionals should ask about black market products “without judgement” so that patients could “be honest about what they have taken”.
Eli Lilly has been developing retatropeptide for nearly ten years. The company is currently working to protect its product and prevent its illegal sale worldwide.
The agency is taking action against peptide companies, influencers, pharmacies, and medical clinics that produce counterfeit drugs. It has filed complaints against more than 14,000 websites, advertisements, and social media posts, alleging that these platforms are illegally selling drugs.
Eli Lilly said: “We will continue to work with law enforcement and regulatory authorities to combat the illicit drug market.”
A company spokesman told the BBC: “Any retatrutide sold online is unauthorised, untested and not worth the risk.”
Over the past year, the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) has carried out several raids and seized numerous batches of products alleged to contain retatropeptide.
The report said these goods enter the UK through a variety of routes and the British government is working to “combate illicit importation and distribution”.
Professor O’Shea said that while we need to “expose the dangers of these drugs traded on the black market”, we must not “abandon these drugs”.
”GLP-1 is a major breakthrough in the treatment of obesity and a significant advance in our understanding of how the brain regulates food cravings and appetite.”
Eli Lilly plans to submit an application for drug registration to the U.S. Food and Drug Administration (FDA) early next year. Because the approval process could take up to a year, retatrutide will not be legally available in the U.S. until at least the end of 2027.
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Post time: Oct-20-2026