A group of scientists is challenging an FDA report released this week warning against the use of kratom, based in part on an FDA analysis that emphasized the substance’s similarity to traditional opioids like morphine and heroin.
“Taken in total, the scientific evidence we’ve evaluated about kratom provides a clear picture of the biologic effect of this substance,” FDA Commissioner Scott Gottlieb said in a statement. “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.”
FDA officials have recommended kratom be categorized as a Schedule 1 drug, which would effectively mean that scientists would not be able to study its effects. Advocates of kratom have long said that the plant-derived substance can be safer than opioid drugs sold at a pharmacy or on the street, fighting pain and treating symptoms of opioid withdrawal without the same, potentially deadly effects on respiration.
Federal officials have occasionally seized imported shipments of kratom on behalf of the FDA, saying it’s a new, untested dietary ingredient. But it’s still widely available, and in most states is readily sold as a dietary supplement in convenience stores, head shops, kratom specialty stores, and online.
“The available science is clear that kratom, although having effects on opioid receptors in the brain, is distinct from classical opioids (e.g. morphine, heroin, oxycodone, etc.) in its chemistry, biological effects, and origin (kratom is a tree in the coffee family, not the opium poppy family),” the scientists wrote, in an open latter to Gottlieb and White House advisor Kellyanne Conway, and circulated by the American Kratom Association, an industry group.
“Importantly, as commonly used in raw plant form, it does not appear to produce the highly addictive euphoria or lethal respiratory depressing effects of classical opioids,” the group, including scientists from Johns Hopkins University, Columbia University and the University of Rochester, wrote. Conway has been overseeing White House efforts to combat the national opioid crisis.
Questions About The FDA’s “Novel” Analysis, Death Estimate
Scientists have known since the ’90s that kratom contains alkaloid compounds that exhibit mild opioid activity. That made the FDA’s warning puzzling–and frustrating–for some researchers.
“I don’t really see what this adds to this field or adds to the body of knowledge around kratom,” Andrew Kruegel, a Columbia University pharmacologist who has extensively studied kratom and signed the letter, told Tonic. “The problem with saying it’s ‘an opioid’ without qualification is that it just paints everything with this broad brush, and obviously carries a negative connotation given what’s going on in the country right now,” Kruegel says.
He also questioned the technique used by the agency, a process known as molecular modeling or molecular docking that attempts to match a computer model of a compound with its receptors in the body. In its warning, the FDA calls it “a novel scientific analysis using a computational model developed by agency scientists, which provided even stronger evidence of kratom compounds’ opioid properties.” But the process tends to be used in the early stages of drug development. “You would not be very confident in the results of that assay,” Kruegel said. “It’s all done virtually in a computer.”
In his analysis, the FDA’s Gottlieb–in addition to comparing kratom to other opioids–also pointed to reports of 44 deaths “associated with the use of kratom.” Skeptics say the deaths can’t be conclusively attributed to kratom and point out that many of the people who died also had other drugs in their systems, from alcohol to morphine.
“They are claiming that 44 people died from a range of causes–including just being completely unexplainable–while also using kratom,” said American Kratom Association chairman Dave Herman in a statement. “Those people who died likely also drank water, a soda, or used hair shampoo in the shower that day.”
Still, the FDA says at least one death report involved someone who reportedly never used any opioids besides kratom, and cautioned against mixing kratom with other drugs.
“Cases of mixing kratom, other opioids, and other types of medication is extremely troubling because the activity of kratom at opioid receptors indicates there may be similar risks of combining kratom with certain drugs, just as there are with FDA-approved opioids,” according to the agency.
The DEA Is Weighing Kratom’s Abuse Potential
In 2014 the FDA issued an import alert that allows U.S. officials to detain imported dietary supplements and bulk dietary ingredients that are, or contain, kratom. But in 2016 the DEA backed away from a plan to ban kratom, amid public and legislative skepticism, and said it would wait for input from the FDA and the public before regulating the drug.
Late last year, the FDA issued a report to the DEA indicating that kratom has no accepted medical use, and the DEA is in the midst of evaluating the drug’s potential for abuse. When that’s done, the agency will determine whether kratom will be restricted, says DEA spokesman Melvin Patterson. The timetable for that decision is still uncertain, he says.
The debate echoes arguments around legal marijuana, especially as the Trump administration reportedly plans to roll back a permissive policy toward states that allow cannabis sales for medicinal or recreational purposes. As with kratom, marijuana proponents and some researchers say that drug is a safe alternative to opioids for some pain patients.