Former CDC Commissioner: Kratom Has ‘Low Abuse Potential’

By Pat Anson

The U.S. Food and Drug Administration has a conflicted and contentious history with kratom, the herbal supplement used by millions of Americans to self-treat their pain, anxiety, and depression.  

Kratom has been used for centuries in southeast Asia as a natural stimulant and pain reliever, but only in the past decade has it become widely available in the United States -- over the strong objections of the FDA.

In 2016, the FDA joined with the DEA in proposing that kratom be classified as an illegal Schedule I controlled substance due to its abuse potential, a request that was later withdrawn due to a public outcry.

That setback didn’t stop then-FDA Commissioner Scott Gottlieb, MD, from launching a public relations campaign demonizing and mischaracterizing kratom as an addictive “opioid.” Gottlieb cited FDA research that an Assistant Secretary for Health later called “embarrassingly poor evidence & data.”

To improved its data, last year the FDA said it would conduct a new study on the risks and safety of kratom, and then abruptly cancelled it without explanation, claiming kratom has a “chemical affinity” with opioids and should not be used to treat medical conditions. “The use of this substance, that has yet to be tested and determined safe for use in human population by the Agency, is a significant concern,” the FDA said.

The claim that kratom “has yet to be tested and determined safe” is misleading, because the FDA had just completed a pilot study showing that kratom is relatively safe, even at doses as high as 12 grams -- the equivalent of taking 24 capsules of kratom leaf powder within five minutes.   

“In 2024, the FDA completed a single ascending-dose clinical trial examining ground kratom leaf in experienced users. The results were illuminating: participants experienced no serious adverse events at doses up to 12 grams, with side effects limited to mild nausea and pupil constriction. Crucially, subjective ‘drug liking’ scores never reached statistical significance compared to placebo, indicating low abuse potential for natural leaf,” former CDC Commissioner Robert Redfield, MD, said in an op/ed published today in The Hill.

Redfield’s comment is notable, because the FDA itself has never had much to say about its 2024 study and still hasn’t posted the final results. According to the American Kratom Association, FDA researchers were "profoundly disappointed” at the lack of adverse events associated with kratom, as that doesn’t square with the agency’s long-held public position on kratom.

Redfield may be reassured of the safety of natural kratom, but he thinks the federal government should take emergency action to ban the import and sale of synthetic kratom extracts, which have elevated levels of 7-hydroxymitragynine, an alkaloiid that is present in only minute amounts in the natural leaf. Kratom extracts have been associated with serious adverse events and overdoses.  

Redfield says synthetic kratom has “pharmaceutical-grade opioid chemistry” and should be taken off the market immediately. But he thinks natural kratom is relatively safe, and cites the 2024 study as evidence.

“This clinical evidence establishes a critical scientific baseline: natural kratom leaf, when used as it has been for centuries, presents a markedly different risk profile than the synthetic products flooding American markets,” Redfield wrote. “This is not about banning kratom. Full spectrum kratom, used responsibly, appears to have acceptable safety margins based on FDA’s own clinical data. This is about preventing synthetic opioids from hiding behind botanical names.”

The FDA still has “serious safety concerns” about natural kratom, but has little evidence to back them up and is apparently slow-walking research. Only two federally-funded kratom studies are currently recruiting participants. One would study the effects of natural kratom and the potential for withdrawal, while the second trial would study the effects of kratom extracts.

Both studies are small and won’t be completed until 2028 —- over a decade after the agency tried to get kratom banned nationwide.