Editor’s note: This story contains mentions of substance abuse and related deaths.
After accepting travel reimbursements and indirect donations from pro-kratom lobbying groups, a UF College of Pharmacy professor has drawn criticism for not disclosing conflicts of interest in his research papers about the substance.
A distant cousin of the coffee plant, kratom tree leaves have been used by farmers and laborers in Southeast Asia for centuries to boost energy, improve mood and manage opioid withdrawal. In the U.S., kratom has gained popularity in its powder, capsule and extract forms as an unofficial treatment for chronic pain and substance abuse.
Christopher McCurdy, a UF College of Pharmacy professor, has been researching kratom’s effects for over two decades. His ties to the American Kratom Association, a group lobbying for kratom regulation instead of bans, were uncovered by ProPublica last month.
On one occasion, the group covered McCurdy’s hotel fees when he spoke at the 2025 meeting of the U.N. Commission on Narcotic Drugs in Vienna, according to a March 3 email between McCurdy and Stephanie Taylor, an assistant for the AKA.
ProPublica also found the AKA paid for McCurdy’s $8,700 first-class plane ticket to Indonesia in 2024. But after he canceled the trip last minute, the AKA insisted he keep the flight credit for future travel, according to an Aug. 23 email between McCurdy and Mac Haddow, the AKA’s lead lobbyist.
McCurdy did not respond to three requests for comment over two weeks by phone call, email and a message left in person with his assistant.
The AKA has defended its relationship with McCurdy and other scientists, denying a conflict of interest.
Lead lobbyist Haddow said the association sponsors travel for experts to present their published research, but it can’t dictate what scientists report at hearings.
“This attack — and it is, without question, an attack — is completely unjustified against the credibility of these scientists,” he said, adding that McCurdy has previously disclosed funding he’d received to speak at hearings like the Georgia Blue-Ribbon Study Committee in June.
However, McCurdy never mentioned the AKA during the 2025 UN narcotics meeting, for which AKA covered his hotel room.
Haddow also confirmed the AKA donated to the University of Florida Foundation to fund the International Kratom Symposium, an event McCurdy founded in 2019.
But he said the AKA has never funded a kratom study for McCurdy, either directly or through its sister organization, the Center for Plant Science and Health.
A controversial substance
The U.S. Food and Drug Administration has declared kratom an unsafe food additive that can’t be legally marketed as an over-the-counter drug or dietary supplement. The FDA advises against using kratom due to a risk of liver toxicity, seizures and risk of addiction.
Among the over 50 active compounds in kratom leaves, the alkaloids mitragynine and 7-hydroxymitragynine (7-OH) are the most studied, according to the National Institute on Drug Abuse. These compounds explain why kratom acts as an energizing stimulant in low doses and an opioid-like sedative in higher doses.
The deaths of two University of Mississippi students brought kratom under further scrutiny after MGM-15 pills, a banned kratom-derived product, were found at both scenes. Court records of an unreleased toxicology report showed the presence of three chemicals from the pills in their bloodstreams, according to Action News 5.
While kratom has also appeared in other toxicology reports, the product is often used alongside other drugs — like cough syrup, in one of the Ole Miss cases — making it hard to determine the students’ exact cause of death.
Researchers and groups like the AKA make an important distinction between natural leaf kratom and synthetic or semi-synthetic derivatives like MGM-15, which contain chemically extracted and boosted levels of 7-OH.
In Florida, kratom is governed under the Florida Kratom Consumer Protection Act, which bans the sale of kratom products to people younger than 21.
Drug or drink of choice?
Natural kratom, which lacks the addictive potential of boosted 7-OH, is the AKA’s poster child and the focus of leading researchers like McCurdy. Although 7-OH is present in natural kratom, it occurs only in trace amounts, making up less than 2% of its total alkaloid content.
Kava Gator Coffee Shop in Bo Diddley Plaza, run by 49-year-old Julia Brensel, serves natural kratom, which it markets as a botanical tea.
To new customers interested in kratom, Brensel will describe its benefits and effects, she said. The drink is made with 5 grams of kratom powder per glass and brewed with lemon juice and water.
“It’s a tea with a kick,” Brensel said, sipping from her own glass of kratom, which she sweetened with a Torani syrup to offset its natural bitterness.
She drinks kratom daily, she said, but she hasn’t felt withdrawal effects when she’s stopped for as long as two weeks in the past during a vacation.
Kava Gator offers three colors, or “veins,” of kratom: white, red and green. Each strain’s effects depend on when the leaves were harvested. White kratom, the least mature, is good for concentration, Brensel said, while red, the most mature, aids with pain relief, and green delivers a wine-like buzz.
Health consequences
Unregulated by the FDA, natural kratom still comes with risk. Those who have seen family members become addicted to its powder form — like Susan Cave, who lost her 32-year-old son — argue everything under the kratom umbrella should be taken off consumer shelves.
William Cave II, who battled depression and anxiety since he was a teenager, first bought kratom powder in his late 20s from a gas station in 2020. While working as a pharmacy technician, one of his coworkers recommended he try it to help with his mood.
“Everything he’d read said it was safe and natural,” Susan said, “and it did make him feel better — about the first six months.”
William eventually noticed he had to start taking higher doses to experience the same effects, she said. A year into taking kratom, he started experiencing withdrawals, including flu-like symptoms, shakiness and fatigue every time he stopped or tried to take lower doses.
An attempt to go cold turkey was "disastrous," Susan said.
On April 20, 2024, William drove to St. Mark’s Lighthouse in Wakulla County — his usual fishing spot — and fell forward into the water, Susan said.
By the time he was dragged onto shore by bystanders, he was dead, she said, and attempts to revive him failed.
Susan initially thought it might have been a heart attack. She only suspected kratom could have caused his death after William’s autopsy report listed mitragynine intoxication, its main active compound.
“I’m like, ‘Holy crap,’” she said. “‘All this stuff he’s been taking, it ended up killing him,’ and of course I’m devastated.”
Kratom’s interactions with other drugs, such as the antidepressants William was taking at the time, remain unclear, but similar cases have been reported. Determining causation would require clinical trials.
Since his death, Susan has told William’s story at hearings and briefings for anti-kratom bills as an advocate for Kratom Danger Awareness, a grassroots movement championing a full ban on the product.
KDA’s founder, 64-year-old Wendy Chamberlain, created the organization in 2020 after the similar loss of her son, 38-year-old Joseph Lumbrazo. Lumbrazo, a father of three, was found dead in his New York home in 2020.
He struggled with an addiction to kratom for the three years leading up to his death, Chamberlain said, ramping up his consumption to deal with long hours at work as a business owner.
The KDA has since grown to over 3,000 members, and Chamberlain has continued to speak against kratom in legislative hearings across the country. Despite receiving hate mail and death threats, including a picture of her home, she doesn’t plan to stop, she said.
“Do I want to be here on this journey?” Chamberlain said. “Absolutely not. I’d rather be listening to my son laugh and tell a joke and be spending time with his kids. I’m hoping one day that this will all be over with, and the government will wake up.”
What bans would mean for future research
This June, an emergency rule placed 7-OH, MGM-15, MGM-16 and four other kratom derivatives on Schedule I of the Controlled Substances Act, the same level as heroin and LSD.
The listing comes with pros and cons, according to natural kratom researcher Marc T. Swogger, who supports stricter regulation over outright bans. One benefit is that it gets 7-OH products out of gas stations, Swogger said, where age verification might be overlooked or sidestepped when purchasing.
But the bad part, he said, is taking the war on drugs even further with kratom.
“As soon as you criminalize something, you've started doing damage in a different way,” he said. “Do we really want to be arresting grandmothers for using kratom for pain?”
After a substance is designated as Schedule I, conducting studies can be challenging, he added, because researchers are required to register with the Drug Enforcement Administration before they can do so.
And further research is crucial to determine the definitive cause in kratom-related deaths, he said. Questions remain, even in deaths where kratom is the only substance involved, because mitragynine in natural kratom causes little to no respiratory depression — the usual cause of death in opioid overdoses.
“The big missing piece here is that we don’t know a mechanism by which kratom would kill a person,” Swogger said. “Unfortunately, because of the way that kratom has been dealt with by the authorities, there's just very little impetus for researchers to get involved.”
Contact Chloe Santiago at csantiago@alligator.org. Follow her on X @csant860.
Chloe Santiago is a junior journalism major with a focus on data and coding. She previously served as one of the Summer 2026 copy editors. Her idea of fun is a scary movie or video game at night with all the lights turned off.
