Kratom is an herbal supplement with a cult following, but new research connects its use with vomiting, confusion, and even seizures

Kratom, a psychoactive substance derived from a relative of the coffee plant, is a hot trend in the herbal supplement world, marketed to treat everything from addiction to pain to post-traumatic stress disorder.

But kratom shot wide availability and lack of regulation has prompted scrutiny from the medical community — and its use has been linked to serious health issues, according to a new study.

Research published in June in the Pharmacotherapy journal looked at more than 2,000 calls to the National Poison Control Center involving kratom use. Of the 935 calls in which kratom was the only substance involved, the most common symptoms were relatively mild, like agitation and drowsiness. Some people, however, reported vomiting, confusion, and, rarely, seizure, respiratory or cardiac arrest, and, in one case, death.

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Among the calls that involved kratom use and other potential toxins, reports of side effects tended to be more severe on the whole. In some cases, kratom users reported seizures or symptoms of psychosis. In three cases, kratom contributed to a death, though other drugs including alcohol, prescription drugs, and cocaine were also involved.

A small subset of patients also reported withdrawal symptoms after using kratom.