FDA Received Reports of Two Deaths Tied to Bootleg Versions of Weight-Loss Drug Retatrutide

The Food and Drug Administration has received reports of two deaths in people who took bootleg versions of retatrutide, an experimental weight-loss drug from Eli Lilly that has not been approved for sale, according to federal records obtained by CBS News.

The reports, filed with the FDA’s Adverse Event Reporting System and released under the Freedom of Information Act, appear to be the first public accounts in the United States linking unauthorized use of the drug, or products claiming to contain it, to a patient’s death. The information has not been verified, and the reports do not establish that the products caused either death.

Two cases, both ending in cardiac arrest

In the first case, reported in July, a health care professional told the FDA that a 41-year-old woman with obesity went into cardiac arrest after taking retatrutide obtained “from an unreliable source.” She was taken to a hospital with a dangerously rapid heartbeat and could not be revived. The report noted she had been drinking kava at the time.

In the second, reported in September, a 49-year-old patient died after experiencing severe dehydration, malnutrition and cardiac arrest. According to the report, a licensed nurse “convinced” her to buy the drug from an online peptide vendor, provided the link, sold her vials and recommended dosages. An image in the report showed a vial labeled “AlphaLabs”; a lawyer for that company’s owner said the redacted report did not contain enough information to determine whether it sold the product and that the vial did not match its current packaging.

A booming gray market

Retatrutide, which targets three hormone pathways involved in appetite and metabolism, has produced greater weight loss in clinical trials than any obesity drug currently on the market, and Wall Street expects it to become a blockbuster. It is supposed to be available only through clinical studies. Neither death was connected to a formal trial, according to the documents and Lilly.

Even so, versions marketed for “research use only” are widely sold online, in med spas and wellness clinics. America’s Poison Centers logged 862 reported exposures to retatrutide in the three months through September, up from 460 in the prior quarter and 249 in the first three months of 2026.

Eli Lilly said the reports “make clear the two individuals were taking black-market retatrutide,” adding that it has found counterfeit products with too much, too little or the wrong active ingredient, as well as contaminants. The company is pursuing legal action against sellers.

Calls for a closer look

The FDA declined to say whether it had verified either report, saying it reviews adverse event reports and gathers more information when needed. Pieter Cohen, an associate professor at Harvard Medical School, urged the agency to obtain and test the products the patients injected, warning that a failure to investigate aggressively would be “deeply concerning.”

Physicians advise patients to use only FDA-approved weight-loss medications obtained through a licensed prescriber and pharmacy.