The botanical substance kratom may be emerging as a small but dangerous piece of the nation's ongoing drug crisis, a new analysis shows.
Made from a plant native to Southeast Asia, kratom can be used as a stimulant in low doses, while at higher doses it can act as a depressant and painkiller. It's often sold at corner stores, smoke shops or online and has become increasingly popular in the U.S. in recent years, although federal agencies consider kratom a drug of concern and research on its effects is limited.
Now, a new study from the Centers for Disease Control and Prevention suggests kratom can be deadly, especially when used with other drugs. An analysis published Thursday involving a sampling of U.S. states says there were 152 drug overdose deaths from July 2016 to June 2017 in which the person who died tested positive for kratom.
Among those fatal overdoses, kratom was listed as a cause of death for 91 people, including seven who tested positive for no other substance, although researchers cautioned that "the presence of additional substances cannot be ruled out." For the majority of deaths, the ultrapotent opioid fentanyl and its analogues were the most commonly co-occurring drugs listed as a cause of death, followed by heroin and benzodiazepines.
Researchers said the number of deaths in which people tested positive for kratom may be underestimated due to differences in toxicology testing.
"The type and number of substances detected in kratom-involved deaths can inform overdose prevention strategies," researchers said. Some states and localitieshave banned kratom outright, while others – including Oregon and the town of Castle Rock in Colorado – have been considering regulations.
Thursday's study involved data from 27 states, though only 11 reported deaths that occurred during the entire period of July 2016 to December 2017. About 80% of the deaths tied in some form to kratom were among people who had a history of substance misuse, CDC researchers said, and most people were not believed to be undergoing "medically supervised treatment for pain."
Kratom is not regulated by the Food and Drug Administration and has not been approved for any medical use, but it's frequently seen as a safer drug alternative and has been used as a means of treating opioid withdrawal, anxiety and other conditions. The FDA has issued several advisories about kratom, warning that it has potential for abuse amid a nationwide drug epidemic that killed more than 70,000 peoplein 2017.
"FDA is concerned that kratom, which affects the same opioid brain receptors as morphine, appears to have properties that expose users to the risks of addiction, abuse and dependence," the agency says.
Meanwhile, nonfatal incidents involving kratom have soared in recent years. A separate study published in Februaryshowed that calls to poison control centers for kratom exposure increased about fiftyfold from 2011 to 2017, with the majority of calls made in 2016 and 2017.
"More research is needed to define the human response to kratom," the February study says. "Individuals who choose to use kratom should be educated about its potential risks, including the dangers of using it in combination with other substances."