CBS News Lab Tests: Brooklyn Bodega Vial Sold as Retatrutide Held No Peptide and 13 Bacteria Colonies

A vial sold over the counter in Brooklyn as an experimental weight-loss drug contained no peptide at all. It did contain bacteria.

That is the finding from a CBS News purchase-and-test investigation published today, Oct. 21. National correspondent Adam Yamaguchi bought products marketed as retatrutide, nicknamed "Reta," from three sellers and sent them to a University of Iowa lab.

Retatrutide is an experimental peptide drug that Eli Lilly is studying as a next-generation obesity treatment. It has not been approved by the FDA. It is in Phase 3 trials, the final stage of clinical testing before a possible approval decision.

Three purchases, no consultation

Yamaguchi's first order was placed through the website of Reset Wellness, a clinic started by a nurse practitioner. He ordered 20 milligrams. At checkout he was promised a health evaluation, but the product arrived a week later and he never spoke to a health professional.

His second order came from the website of Bodystreet Jupiter, a gym in Florida. He first confirmed he met the site's body mass index requirement. The site said a doctor would review his intake form. The product showed up two days later with no consultation.

The third purchase was the easiest. He found a poster advertising the product at a Brooklyn bodega and bought a vial labeled "Retatrutide" for $90. The label read "Research use only, not for human consumption."

What the lab found

Jason Galpin, a University of Iowa research scientist, analyzed the samples for CBS News. Both online samples were consistent with a basic standard he created for retatrutide. Galpin's standard is not the same as the drug being tested in Eli Lilly's clinical trials, so the results do not show the products match the trial drug.

The bodega sample was different. "It does not look anything like a peptide," Galpin said.

Instead he found phenylacetic acid, which he described as a filler commonly found in fragrances and lip balms.

Carl Ross, director of development at the University of Iowa's Center for Biocatalysis and Bioprocessing, tested the same sample and found 13 colonies of bacteria. Ross warned that injecting contaminated material could cause infection.

"As kids, we're all taught to wash out cuts if we get cut, but in this case … we're injecting bacteria under the skin where it could multiply," Ross said. "It's pretty terrifying."

The gap between a checkout page and a doctor

Dr. Reshma Ramachandran, a Yale physician who has studied the growing use of peptides and weight-loss drugs, called it "astounding" how easily these drugs can be had. She said people who try products labeled as retatrutide are essentially acting as guinea pigs, because the drug is still in trials and has not been certified as safe and effective.

She said prescribing should involve a conversation about a patient's medical history, the risks and whether the treatment fits. In two of the three purchases, that conversation never happened despite the sellers' stated promises of review.

Ramachandran said she hopes regulators can find ways to oversee these platforms as access grows. No new rule or enforcement action has been announced.

What buyers are reporting

A separate University of Pennsylvania study, published in JAMA Network Open, looked at how people describe using gray-market retatrutide. Researchers used AI to analyze nearly 150,000 Reddit posts and comments from roughly 40,000 users.

Among reports that could be classified, increased appetite was the most frequent symptom, after expected effects such as weight loss and appetite suppression were excluded. That differs from Phase 2 trials, where nausea and other gastrointestinal complaints were the most common side effects.

Compared with the team's earlier work on semaglutide and tirzepatide, retatrutide posts had proportionally more reports of appetite-related symptoms, sleep disturbances, increased heart rate and muscle-related changes. Gastrointestinal complaints were proportionally less common.

The authors cautioned against reading too much into it. "We can't say that retatrutide is causing these symptoms, or even that Reddit users are actually taking genuine retatrutide, since the drug is not legally available, and gray market formulations vary," said Lyle Ungar, a Penn computer and information science professor and co-author.

Co-author Jena Shaw Tronieri, of Penn's Center for Weight and Eating Disorders, noted the people posting may also differ from trial participants. Her point lines up with the lab results: buyers cannot know what is in the vial.

What comes next

The only legal route to retatrutide is the one Lilly is running. Until its Phase 3 trials finish and the FDA rules, every vial on the market is unapproved, and the Iowa tests show that what a label says and what a vial holds can be entirely different things. Whether any regulator moves against the sellers is an open question.