A member of the coffee family, kratom is a tropical tree that grows naturally in Thailand, Indonesia, Malaysia, Myanmar, and other parts of southeast Asia. Leaves from the tree can be crushed and then smoked, brewed with tea, or placed into gel capsules.
So why is it listed as a Drug and Chemical of Concern by the Drug Enforcement Administration (DEA)?
Federal officials say kratom is addictive and can produce an opioid-like high and has psychoactive properties. Since the drug is not yet illegal, it's currently marketed and sold in the U.S. as an alternative to controlled substances.
Advocates have made a huge push in recent years to keep kratom legal, most recently staging a protest in Washington, D.C. Users say it's a safe plant-based alternative to painkillers that can treat pain, anxiety, and depression.
Use of the drug can give users either sedative or stimulating effects, according to researchers. In lower doses, the drug acts as a stimulant and can make a person more talkative, sociable, and energetic. It higher doses, it can give the user feelings of lethargy and euphoria.
Users quickly feel the effects of kratom, which can last between five and seven hours, or even longer in higher doses. The Food and Drug Administration (FDA) is concerned that some users take it for its euphoric effects, which they believe can lead to abuse of the drug.
Kratom's effects on the body include nausea, itching, sweating, dry mouth, constipation, increased urination, tachycardia, vomiting, drowsiness, and loss of appetite. Users of kratom have also experienced anorexia, weight loss, insomnia, hepatotoxicity, seizure, and hallucinations.
Several cases of psychosis resulting from kratom use have been reported, where individuals addicted to kratom exhibited psychotic symptoms, including hallucinations, delusion, and confusion.
Officials with federal agencies like the DEA and FDA are becoming concerned because kratom is growing in popularity in the U.S. to treat symptoms of opioid withdrawal amid a nationwide crisis of opioid abuse.
Between 2000 and 2005, the American Association of Poison Control Centers reported two exposures to kratom. Between 2010 and 2015, U.S. poison centers received 660 calls related to kratom exposure. There were 15 kratom-related deaths between 2014 and 2016, according to the DEA.
Authorities say because the identity, purity levels, and quantity of kratom substances are uncertain and inconsistent, they pose significant adverse health risks to users. That's why the FDA has not approved kratom for any medical use and the DEA has listed it as a Drug and Chemical of Concern.
Over 55,000 kilograms of kratom material was encountered by law enforcement at various ports of entry within the U.S. between February of 2014 and July of 2016.
While kratom is still not illegal on a federal level, several states have regulations or laws against the possession and use of kratom. The long-term effects of kratom and possible benefits of the drug, if any, are still being studied.
See more about kratom in Elizabeth Vowell's special report on 9News at 10.