Four deaths in Utah have been linked to potent semi-synthetic kratom compounds, state officials said Monday. The kratom-derived compounds, mitragynine pseudoindoxyl (MGPI) and dihydro-7-hydroxymitragynine (MGM-15), are illegal in the state and were recently classified by the Drug Enforcement Administration as Schedule 1 drugs. Both are semi-synthetic derivatives of kratom.

Utah health, poison center and agriculture officials warned that the compounds were found in certain herbal supplements, including kratom products, as well as products labeled “cat’s claw.”Cat’s claw is not a harmful supplement, but testing in these cases revealed it contained MPGI and MGM-15, the statement said.

The warning said that the products were “often sold under brand names like ‘Buzzers’ and are misleadingly labeled as containing ‘cat’s claw’ or its scientific name Uncaria tomentosa.”The labels, officials said, often claim the product is “legal and free of kratom, yet warn it is for ‘adults only/21+’ or produces strong psychoactive effects.” (The warning does not directly link the Buzzers’ products to the deaths.) “These cat’s claw products contain dangerous opioids derived from kratom,” said Dr. Michael Moss, the medical director of the Utah Poison Control Center. “No one should take these products, retailers should not sell them, and healthcare providers should be aware of potential for addiction, withdrawal, and overdose related to their use.”

Experts say that cat’s claw, which comes from a South American vine, is generally safe. It’s taken by some people for its anti-inflammatory properties. Kratom is used for pain relief, depression and opioid withdrawal but is highly addictive and can cause overdose and death in extreme cases. Neither are approved by the Food and Drug Administration. The agency says kratom is not appropriate for use as a dietary supplement. Exo Club, which makes Buzzers, did not immediately respond to a request for comment.

On its website, it says the product does not contain kratom. “We extract an indole alkaloid from the Cat’s Claw plant to mirror the effects of popular kratom products,” the website reads. In recent months, Utah has noticed calls to poison control about cat’s claw products, which experts say do not cause harmful side effects. People were instead reporting symptoms that resemble an opioid overdose, Moss previously told NBC News.

Several other states have also recently issued warnings about products labeled to be cat’s claw but contained compounds related to kratom. Tennessee issued its own warning in September after the state’s Bureau of Investigation found the synthetic kratom compound MGM-15 in cat’s claw products. In Virginia, the Blue Ridge Poison Center has also received calls about cat’s claw products that caused opioid-like effects. Kratom is banned in at least 10 states, and many others regulate it or have bans on specific kratom-related compounds.

Last year, the FDA recommended the Justice Department classify 7-hydroxymitragynine, or 7-OH, an opioid found in the kratom plant, as an illicit substance. This summer, the DEA announced its intent to do so, but has not yet done so. It has, however, temporarily classified several other kratom-related compounds, including MGPI and MGM-15, as Schedule 1 drugs. According to a report from the Centers for Disease Control and Prevention, 233 deaths were linked to kratom from 2015 to 2025.

TMZ reported that, according to the medical examiner’s office in Nashville, Tennessee, Grammy-nominated record producer Tay Keith, 29, whose real name was BryTavious Chambers, had a kratom chemical and ketamine in his system when he was found dead in June. In 2023, the family of a Florida woman was awarded $11 million in a wrongful death lawsuit after the coroner attributed her death to “acute mitragynine intoxication,” referring to a compound found in kratom.

In Mississippi, investigators are looking into the deaths of two University of Mississippi students in September. Packaged kratom was found at the scene of both deaths.