The Therapeutic Goods Administration has confirmed that an Australian patient suffered a torn esophagus after using a counterfeit weight-loss peptide product labeled as retatrutide. Laboratory testing by the TGA found the product contained no retatrutide whatsoever. Instead, it contained undeclared semaglutide — the drug used in approved products like Ozempic and Wegovy — at a dose approximately eight times higher than that found in TGA-assessed semaglutide products.
The case adds to a growing pattern of serious injuries tied to fraudulently labeled gray-market peptides in Australia. Earlier reporting documented acute liver damage hospitalizations in Victoria linked to contaminated counterfeit retatrutide. This latest case involves a different patient, a different mechanism of injury, and a different mislabeled compound — high-dose semaglutide causing esophageal trauma rather than liver toxicity.
The findings follow product testing conducted by ABC in partnership with the University of Queensland.
What happened
The TGA conducted laboratory analysis of a weight-loss peptide product sold under the label retatrutide, an unapproved compound. Testing confirmed the product contained zero retatrutide. Instead, it contained undeclared semaglutide at a concentration roughly eight times the dose present in TGA-assessed semaglutide products.
A patient who used the product suffered a torn esophagus, a serious injury documented as an adverse event linked to the counterfeit substance.
This incident is distinct from previously reported cases in Victoria, where patients were hospitalized with acute liver damage after using counterfeit retatrutide products found to be contaminated. In those cases, the mechanism of harm involved liver toxicity. In this case, the harm stemmed from an undisclosed high dose of semaglutide.
Why it matters
The case illustrates a specific and severe form of patient harm arising from fraudulent peptide labeling. Products marketed as one compound can contain entirely different substances at dangerous doses, with no disclosure to the consumer.
For consumers purchasing peptides through gray-market or online channels, the risk extends beyond impurities or contamination. The active ingredient itself may be misidentified, and the dose may far exceed what any regulated product would contain.
For telehealth platforms and prescribers, the case underscores the danger of recommending or facilitating access to unapproved peptide products whose contents cannot be independently verified.
For regulators, the torn esophagus adds to a documented series of serious adverse events — including liver damage — linked to counterfeit retatrutide in Australia, reinforcing concerns about the unpredictability of black-market peptide products.
What to watch next
- Whether additional adverse events linked to counterfeit retatrutide or other mislabeled peptides emerge in Australia or other jurisdictions
- Whether the TGA escalates enforcement actions against distributors of counterfeit peptide products
- Whether telehealth platforms and prescribers adjust recommendations in response to documented injuries from unapproved peptides
- Whether regulators in other countries issue parallel warnings about counterfeit retatrutide products
Sources
Industry information only. Not medical or legal advice.
