Plucked from the tree

Published July 01 2017

In the Malaysian countryside, shown here in an aerial view, some residents cultivate their own kratom trees.

While human studies involving kratom haven’t taken place in the U.S., the plant’s prevalence on the other side of the Pacific Ocean allows for a wealth of observational studies in Malaysia, where the plant is nominally illegal under an amendment to the Poisons Act of 1952.

According to Darshan Singh, an epidemiologist at the University of Science Malaysia, kratom users in Malaysia generally fall into three groups.

Older, rural kratom users typically use the plant for its low- and medium-dose effects as a stimulant and painkiller, respectively. “If you look at the rural areas, you get to see people cultivating their own kratom tree behind their house. Cultivation of kratom trees is not a serious offense in Malaysia, but possession and misuse of kratom leaves can put someone in serious trouble with the law. So if they want to use kratom or they want to drink kratom juice, they will just have to pluck fresh kratom leaves and boil it for personal consumption,” says Singh.

Younger users seeking a high consume kratom in a beverage called chakroi that combines processed kratom juice with cough syrup, which contains the antihistamine diphenhydramine. Because juice from kratom leaves tends to be bitter, Singh says, the users typically add Coke or Pepsi as a caffeine-containing sweetener. The beverage is also popular in Thailand, where it’s known as 4X100, or sii koon roi. Thailand has reported one death involving kratom consumption.

“Nobody has died because of kratom use in Malaysia,” says Singh. “You also have illegal kratom traders in the community, people who are selling fresh kratom juice, but it’s actually very safe.”

The third group of kratom users bears the most resemblance to those in the United States. “They use kratom to self-treat their heroin-addiction problem,” says Singh. “I get to see a lot of heroin users who are on methadone treatment. They don’t want to use methadone, because methadone has a lot of side effects.” Instead, they turn to kratom.

Singh has been monitoring the health impacts of long-term kratom use, which he defines as 10 years of moderate consumption or five years of heavy consumption — around four glasses of boiled kratom juice each day. He and his colleagues at the Center for Drug Research recently completed clinical evaluations of a substantial number of regular kratom users and are preparing to publish the results. They will be soon conducting a study to document the prevalence of kratom use in illicit drug users in Malaysia.

“We found that long-term kratom use does not cause major psychiatric problems like methamphetamine or heroin,” says Singh. “The only problems that you see are slight anxiety and depression problems during kratom cessation in regular kratom users.”

He and his colleagues also noted that long-term kratom use doesn’t appear to cause any cognitive impairment. “There is no impairment in memory, there is no impairment in attention — nothing,” he says.

Despite these findings, Singh is concerned that Malaysian authorities might reclassify kratom from its current status as a poison to that of a fully outlawed compound. “They’re in limbo over whether to do that or not, because they see a lot of people are misusing kratom, but I’m trying to make them understand that people who are misusing kratom are people who were dependent on illicit drugs before, and they are beginning to use kratom to treat their dependence,” he says.


John Arnst John Arnst is ASBMB Today’s science writer. Follow him on Twitter.