The FDA says the incidents “underscore the serious and sometimes deadly risks” of kratom, but the list contains a number of events in which kratom played an uncertain role, including a case in which a teenager hanged himself, and another in which a drug overdose victim tested positive for nine different substances.
As a whole, the data suggests the FDA is basing its warnings about kratom’s fatal harms on a patchwork of loosely sourced anecdotal reports that say very little about how the drug is responsible for the fatalities ― or even whether it is at all.
In a press release Tuesday, FDA Commissioner Scott Gottlieb sought to reinforce a November public health advisory in which he claimed there was “clear data on the increasing harms associated” with kratom. At the time, the FDA said it was aware of 36 deaths involving kratom, which it held up as evidence of the gravest of the drug’s potential harms. The FDA has found eight additional cases since then, Gottlieb said Tuesday, bringing the total number of kratom-associated deaths to 44. He also announced the agency had conducted a “novel scientific analysis” of kratom that further supports the FDA’s characterization of the substance as an “opioid.”
“This new data adds to our body of substantial scientific evidence supporting our concerns about the safety and abuse potential of kratom,” said Gottlieb. “As the scientific data and adverse event reports have clearly revealed, compounds in kratom make it so it isn’t just a plant — it’s an opioid.”
Kratom is an herb derived from the leaves of a Southeast Asian tree related to coffee. It’s sold in the U.S. as an unregulated herbal supplement and commonly taken in powder form in capsules or tea. Kratom has opioid-like effects and is often used as a mood enhancer, or for its stimulant or sedative qualities, which can vary depending on the dose and strain. Supporters regularly tout it as a natural treatment for conditions like chronic pain, anxiety and depression. Others claim it’s a safer alternative to traditional opioids, both legal and illegal, which has also contributed to kratom’s increasing popularity as a step-down treatment off of painkillers or heroin.
But due to the lack of regulations around herbal supplements, kratom is largely free from consumer standards on quality or dosing, leading to fears about the possible adulteration of products and problems related to improper self-medication or misuse by youth. The FDA has maintained that kratom is dangerous, and has pointed to the lack of an approved medical use as justification to impound numerous shipments of kratom products into the U.S.
On Tuesday, Gottlieb reiterated concerns about kratom’s “potential for abuse, addiction, and serious health consequences; including death.” As proof of the drug’s deadly harm, the FDA released reports on 36 deaths involving the use of kratom, culled from academic research, medical examiner reports and adverse event reports. Gottlieb also said the FDA plans to release the eight newly received reports.
Almost all of the FDA’s cases involve subjects who were found to be on multiple substances at the time of their death, with the vast majority including either illicit or prescription drugs that carry well-known fatal risks.
One incident describes a teenager who had hanged himself after struggling with depression and prescription drug abuse. He tested positive for a variety of drugs, including kratom, as well as alcohol and a handful of prescription drugs.
Another case involves a man who had fallen out a window, broken his arm and refused treatment before dying. He was ultimately found to have had nine different substances in his bloodstream, among them mitragynine, the primary psychoactive substance in kratom.
FDA’s list of kratom-related deaths also includes a 43-year-old man determined to have died from complications due to deep vein thrombosis. He had a long list of medical problems, including chronic back and shoulder pain and a history of alcohol and prescription drug abuse. At the time of his death, he’d recently been prescribed five different medicines. His toxicology test came back positive for opioids, benzodiazepines ― best known as Xanax ― anti-depressants and a medication apparently used to treat his Tourette’s syndrome. He also tested positive for kratom.
One case the FDA listed as a kratom-related death, which has been completely redacted in the document, appears elsewhere in an agency database as a death by homicide due to a gunshot wound to the chest.
Nine of the FDA’s 36 documented deaths were related to a string of fatal overdoses in Sweden in 2010, which involved a controversial kratom-based product that had been adulterated with a dangerous synthetic opioid. An additional eight cases that FDA previously released to HuffPost consisted largely of voluntary reports, including accounts from family members who simply suspected their loved ones had died from kratom use.
Just one of the FDA’s cases appears to involve the presence of kratom alone, though the report includes no information on the death apart from the subject’s age and ethnicity. The report shows the individual tested positive for high levels of mitragynine, but as in the rest of the cases, says nothing about how the substance was determined to have contributed to his death. The FDA denied HuffPost’s request for additional information on that case.
In his Tuesday statement, Gottlieb said the agency is investigating another kratom-related death involving an individual who “had no known historical or toxicologic evidence of opioid use, except for kratom.”
Taken together, the FDA case reports provide no clear picture of the “deadly risks” the agency claims kratom poses. There’s also a certain irony in the fact that so many of the deaths the FDA associates with kratom also appear to have involved prescription drugs, which it argues must be safer than kratom.
In fairness to the FDA, it has acknowledged the limitations of the reporting systems used to compile these deaths. On its website, the FDA says the inclusion of a case doesn’t imply a “causal relationship” between a product and an event. It also notes that “reports do not always contain enough detail to properly evaluate an event.”
Gottlieb appears to be at least somewhat aware of these constraints.
“Many of the cases received could not be fully assessed because of limited information provided,” he said in the statement, adding that “a few” cases “raise concern that kratom is being used in combination 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,” Gottlieb said.
Glottlieb specifically referenced prior FDA warnings about kratom’s side effects, including “seizures and respiratory depression.” But these potentially deadly symptoms don’t appear in any sort of discernible pattern in the cases the FDA cites, and they’re not well-documented elsewhere. While scientific studies on the effects of mitragynine on humans are still lacking ― largely because it’s difficult to get funding for research on a plant that can’t be patented ― most of the emerging science on kratom has found it to be largely benign, especially when taken in low or moderate doses.
Andrew Kruegel, a Columbia University chemist, has authored a number of studies on the pharmacology of kratom. On Tuesday, he questioned Gottlieb’s conclusion that the substance is simply an “opioid,” a conclusion the commissioner based off the FDA’s use of computational modeling on the chemical structures of kratom’s compounds.
“They don’t have to do this to claim that kratom is an opioid, because it is,” said Kruegel. “But the question is whether it’s an atypical opioid, which is my preferred terminology. Does it have a better side-effect profile than the classical opioid drugs like morphine that we use every day? That’s the key question here.”
Kruegel added that the FDA’s analysis was “an order of magnitude less rigorous than” many of the studies that had already been conducted on kratom. He said the FDA’s claim was akin to “saying that all opioid agonists have the same effect, which is not true based on what we’ve learned about these compounds.” (Opioid agonists provide pain relief by binding to opioid receptors.)
The FDA’s presentation of kratom-related deaths appears to follow a broader practice, in which officials seem to be determining that any fatal incident involving kratom must therefore be related to the drug. But this haphazard characterization of kratom’s supposed deadly risks does nothing to expand our understanding of how the drug supposedly kills people, if it does at all. And in fact, lumping these cases together despite their obvious dissimilarities may end up producing a misleading narrative about kratom’s actual effects, said Leo Beletsky, an associate professor of law and health sciences at Northeastern University.
“You have to identify and isolate the effect of the drug, and the only real way to do that is through randomized controlled trials or really robust observational evidence,” he said. “We don’t have that.”
FDA’s data could have severe implications for the future of kratom. The latest press release comes as the agency appears to be leading a push to ban the substance under federal law. Following pushback, the U.S. Drug Enforcement Administration postponed a move to place kratom in Schedule I, alongside drugs like heroin and LSD. But the FDA recently completed an analysis that may help determine how the DEA proceeds. A spokesperson for the DEA said Tuesday that it could take “months or even years” for the agency to reach a final decision on scheduling.
Based on the FDA’s recent public actions, however, it appears to favor outright prohibition, a move that would cut off millions of Americans ― many of whom have struggled with opioids or other prescription drugs ― from their preferred method of treatment. Some drug policy experts and a handful of congressional lawmakers have said the damage caused by forcing people away from kratom, and possibly back onto other prescription or illicit drugs, would far outweigh the current harms. Furthermore, if kratom were to be banned, many individuals would simply continue buying and using it illegally. If feds are worried about controlling kratom now, driving it onto the black market will only make that harder.
Beletsky admitted there was still a lot of “uncertainty” surrounding kratom, and said it warrants further research to better understand its full range of effects and possible harms. But considering there are an estimated 3 to 5 million kratom users around the U.S., according to industry figures, he added that the relatively low number of supposed kratom-related deaths ― even in questionable cases like these ― could actually suggest that kratom is not very harmful.
“The only times we’ve found kratom to be involved in adverse events are times when even in the absence of kratom, you’d still have really deleterious effects,” he said. “I worry that by taking these kratom-involved adverse events and painting them as kratom-caused adverse events, we’re going to run into a misclassification of what the problem is, and then, as a result, we’re going to deploy policy solutions that are based on that faulty classification.”