A growing black market for the unlicensed weight-loss drug retatrutide is being driven by TikTok fitness influencers and online sellers operating through Telegram and WhatsApp, a Guardian investigation has revealed.

Despite still being in clinical trials, retatrutide is being advertised online for its supposed fat-burning benefits. Influencers are urging followers to contact them privately for supply information, often sharing discount codes and promoting anonymous sellers.

Beyond TikTok, Telegram has become a key platform for distributing retatrutide, with groups boasting thousands of members. These groups routinely share before-and-after photos, injection tutorials, and claims of next-day delivery across the UK. Transactions typically shift to WhatsApp, where sellers provide payment details and shipping information.

According to the investigation, retatrutide, developed by US pharmaceutical company Eli Lilly, targets three gut hormones, GLP-1, GIP, and glucagon. Early-stage trials suggest it may help users lose up to 25% of their body weight, earning it the nickname "triple G" and comparisons to other popular drugs like Ozempic.

Telegram channels booming with sales and injection guides

However, health professionals warn that the unregulated sale of retatrutide poses serious risks. Since the drug is not licensed for use in the UK, selling or promoting it violates the Human Medicines Regulations 2012.

Some influencers attempt to bypass restrictions by labeling the drug a "research chemical" or stating it's "not for human consumption." Others avoid direct mentions altogether, instead urging followers to PM for details.

According to the investigation, prominent influencers named in the report, such as Jon Kluth, @MappyMyGains, and @clairejoy86, have had their accounts taken down after promoting the drug. TikTok stated that it has removed harmful content and banned associated hashtags.

Inside Telegram groups, sellers offer either powder vials, mixed with sterile water at home, or pre-filled pens, sold for around £160. One seller, when asked whether the product was genuine, admitted: “You can’t be sure.”

Eli Lilly condemns unauthorized sales of the Trial Drug

A spokesperson for Eli Lilly confirmed that retatrutide remains in phase 3 clinical trials and has not been approved by any health authority globally. "At this time, no one can sell [it] for human use,” they said. Products falsely marketed as Eli Lilly's investigational drug “may expose patients to potentially serious health risks.”

Experts across the UK’s health sector are sounding alarms. Jason Murphy, head of pharmacy at Chemist4U, warned: “People are injecting substances they can’t verify. Even if the science behind retatrutide is sound, these versions may not contain what they claim.”

Dr. Crystal Wyllie of Asda Online Doctor said rising costs of approved weight-loss treatments, like Mounjaro, have pushed users toward risky alternatives. “Counterfeit injections are extremely dangerous. You can’t be sure what’s inside, or if it was made in a sterile environment,” she said, noting her team has already treated patients harmed by self-injected substances bought through social media.

A spokesperson from Telegram said the platform actively moderates harmful content, including drug-related promotions, and removes millions of violating posts daily. Still, public channels offering retatrutide remain active and easily searchable.