Calls to US poison centers involving kratom, a psychoactive substance widely sold in gas stations and vape shops, rose sharply over the past decade, reaching a record high in 2025, a new study showed.

An analysis of the National Poison Data System, which captures reports from 53 US poison centers, identified 14,449 kratom-related exposures between 2015 and 2025. Annual cases over the decade climbed from 258 to 3434, a roughly 1200% increase. The largest rise in reports was in adults aged 40-59 years, with rates comparable to younger adults for the first time.

The increase coincided with broader kratom availability and the emergence of higher-potency products that are largely unregulated at the federal level, the authors reported. The rise was also accompanied by parallel increases in hospitalizations and severe outcomes, including 233 deaths during the study period, most involving multiple substances.

“These findings indicate that kratom use is increasing and expanding across demographic groups, underscoring a growing public health concern,” lead author Chris Holstege, MD, director of the Blue Ridge Poison Center at the University of Virginia School of Medicine, Charlottesville, Virginia, and colleagues wrote. “Ongoing surveillance could help identify high-risk patterns of use and inform public health education and clinical care, particularly in cases involving multiple substances.”

The study was published online on March 26 in the CDC’s Morbidity and Mortality Weekly Report.

Growing Kratom Use

Kratom (Mitragyna speciosa) is a tropical tree native to Southeast Asia. Its leaves contain psychoactive compounds, primarily mitragynine and 7-hydroxymitragynine, that act on opioid receptors. Traditionally consumed as a brewed tea, it is now widely available in the US as powders, capsules, and concentrated liquid shots.

The plant is unusual in that it can function as both a stimulant and a sedative, depending on dose. At lower doses, kratom may produce stimulant-like effects; at higher doses, it is associated with sedation and analgesia.

Although it interacts with opioid receptors, kratom is a plant-derived alkaloid, not a traditional opioid.

As previously reported by Medscape Medical News, kratom has gained popularity in the US over the past decade, with estimates ranging as high as 16 million users and more than $2 billion in retail sales.

The shift from natural leaf to high-potency alkaloid extracts has heightened concerns about significant health risks, including liver toxicity and seizures. Kratom is not approved by the FDA for any medical use, and regulators warn that its use is associated with dependence, withdrawal, and severe health consequences.

‘Concerning Trend’

The study showed that polysubstance use posed the greatest risk in kratom-related exposures. Although 62% of exposures involved kratom alone, those involving additional substances were more likely to result in hospitalization and death.

Hospitalization rates were consistently higher in polysubstance exposures (44%-56%) than in single-substance cases (24%-29%). Over the 10-year period, nearly 80% of reported deaths related to kratom involved other substances (184 of 233).

Intentional misuse accounted for about half of exposures. Suspected suicide attempts were reported in 23% vs 6% of multiple substance exposures vs single-substance cases.

Based on these results, the authors called for broader efforts to monitor use patterns and reduce risk.

“The findings in this report describe the impact of the rapidly evolving kratom market and highlight the important role poison centers can play as an early warning surveillance system,” the authors wrote.

They added that enhanced surveillance and public education could help address risks tied to widespread availability, limited regulation, and high-risk multisubstance use.

“The data reflect a concerning trend,” Holstege said in a press release. “This trend found in the national data is also occurring in our local clinical practice.”

The authors noted several limitations. Poison center data rely on voluntary reports and likely underestimate less severe cases. Some reports may reflect repeat callers, and misclassification of substances or outcomes is possible. The data also do not distinguish between traditional kratom products and newer, high-potency formulations. In cases involving multiple substances, it was not possible to determine which substance contributed most to the outcome, the researchers reported.

Disclosure information for study authors is available in the original study publication.