FDA's scientific evidence on the presence of opioid compounds in kratom, underscoring its potential for abuse

FDA has released details on some of the key scientific tools, data, and research that have contributed to the agency's concerns about kratom's potential for abuse, addiction, and serious health consequences. FDA Commissioner Scott Gottlieb said the agency has been particularly concerned about the use of the botanical substance to treat opioid withdrawal symptoms, noting there is "no reliable evidence to support the use of kratom as a treatment for opioid use disorder and significant safety issues exist." Federal agencies must move quickly to assess the abuse potential of newly identified designer street drugs for which limited or no pharmacological data are yet available. FDA has thus created the Public Health Assessment via Structural Evaluate (PHASE) methodology, which helps simulate, using 3-D computer technology, how the chemical constituents of a substance are structured at the molecular level, how they behave inside the body, and how they can potentially affect the brain. Using this model, FDA scientists analyzed the chemical structures of the 25 most prevalent compounds in kratom and found that they all share the most structural similarities with controlled opioid analgesics, such as morphine derivatives. The computational model also predicted that some of the kratom compounds may bind to the receptors in the brain that may contribute to stress responses that affect neurologic and cardiovascular function. The 3-D image generated showed that kratom has a strong bind to mu-opioid receptors, comparable to scheduled opioid drugs. Gottlieb explained, "Based on the scientific information in the literature and further supported by our computational modeling and the reports of its adverse effects in humans, we feel confident in calling compounds found in kratom, opioids." He said FDA now has data on 44 reported deaths associated with kratom, up from the 36 reported in a November advisory. One new report of death was of particular concern, as the individual had no known historical or toxicologic evidence of opioid use, aside from kratom. Based on the findings, Gottlieb noted, "kratom should not be used to treat medical conditions, nor should it be used as an alternative to prescription opioids. There is no evidence to indicate that kratom is safe or effective for any medical use."