Kratom Confusion: An Emergency Physician's Perspective

This editorial is reprinted without references from the Cleveland Clinic Journal of Medicine (August 2026, 93 (8) 493-495; doi.org/10.3949/ccjm.93a.26031). The open-access and fully referenced original article is available at https://www.ccjm.org/content/93/8/493.

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By John R. Queen, MD

For hundreds of years, people in Southeast Asia have used the leaves of the kratom tree as a stimulant, analgesic, sedative, antidiarrheal, and cough remedy. In 1839, the Dutch colonial botanist Pieter Willem Korthals studied and named the tree Mitragyna speciosa, classifying it in the same botanical family as coffee. Now, kratom has become a drug of abuse in the United States and is openly available in stores in a variety of formulations.

This drug is anything but simple, and there is much confusion about who is using it, what it does, and what we physicians should do about it.

Who's using it?

A 2021 study by Palamar revealed that more than 1 in 200 US adults had used kratom in the previous year. The prevalence of its use was significantly higher in those between 18 and 49 years of age, men, and those with a history of substance use disorder or depression. Regarding substance abuse, kratom users were also much more likely to abuse alcohol, opioids, marijuana, cocaine, other stimulants, sedatives, and hallucinogens.

Polysubstance use can make kratom use hard to recognize. Emergency and primary care physicians can attest that patients who use drugs often do not provide a clear or accurate history. I have seen many patients who were mistaken as to which drug they took and had positive tests for substances that they denied taking. To add to the confusion, kratom is known by multiple street names such as thang, kakuam, thom, ketum, and biak.

What does it do?

There are more than 40 known alkaloids in kratom. However, mitragynine and 7-hydroxymitragynine are the two that cause the effects for which people take this drug. Mitragynine is present in greater amounts and is responsible for stimulant effects via serotonergic activity and sedation via partial agonism at the mu-opioid receptor. At lower doses, the stimulant effects predominate, but higher doses result in analgesia and mild sedation.

Seven-hydroxymitragynine is present in smaller amounts but has more mu-opioid receptor activity, causing analgesia and euphoria and possibly resulting in dependence. Despite the mu-opioid receptor activity, kratom is not classified as an opioid.

Adverse effects most commonly reported in individuals who use kratom include agitation, tachycardia, drowsiness, vomiting, and confusion. Withdrawal symptoms can occur when regular use is interrupted or discontinued. These include psychological symptoms such as anxiety, depressed mood, irritability, and restlessness. Physical withdrawal symptoms are similar to opioid withdrawal symptoms (e.g., diarrhea, lacrimation, rhinorrhea, yawning, myalgia and arthralgia).

Kratom packages — Ohio vape shop advertising kratom for sale in the front window. Photo by John R. Queen, MD.

Evolving legal status

Kratom was unregulated until 1943, when Thailand made its distribution and use illegal. Later, Malaysia and Myanmar followed suit.

In the United States, kratom’s status is unique and evolving. Although not currently a controlled substance, it is listed by the US Drug Enforcement Administration as a drug and chemical of concern, and the US Food and Drug Administration has not approved it for any medical use.

Also, kratom is illegal in nine states (Alabama, Arkansas, Connecticut, Indiana, Kansas, Louisiana, Tennessee, Vermont, and Wisconsin) and the District of Columbia. Ohio has banned all synthetic kratom products, but not natural kratom, much to the disappointment of Ohio’s governor, Mike DeWine, who submitted a recommendation to the Ohio Board of Pharmacy that all kratom products be classified as schedule I substances.

Adding to the confusion, kratom is legal in the state of California but banned in multiple municipalities such as Anaheim, Oceanside, and San Diego, and unincorporated areas of Orange County.

Challenges for physicians

Kratom use is not especially common in the United States compared with other illicit drugs, and the common urine drug tests do not detect it. Many clinicians may have little or no experience in treating patients who use or abuse it.

Kratom use is concentrated among individuals with substance use disorders and chronic pain. Its pharmacologic profile — combining stimulant and opioid-like effects — creates diagnostic and management challenges for clinicians. Physicians must recognize that kratom can mimic, modify, or coexist with opioid toxicity, particularly in the era of widespread fentanyl exposure. Awareness of its clinical presentation, the limitations of toxicology screening, and its frequent role in polysubstance use is essential for safe and effective patient care.

Physicians must also be aware of drug use patterns as well as the legal status of kratom in the city and state where they practice to best be prepared to promptly diagnose and treat patients presenting with suspected drug use, abuse, and overdose.

In the future, I expect that the use of kratom will continue to increase as states and municipalities react to this unusual drug. Emergency, primary care, and other physicians will be challenged to remain current with their knowledge of the diagnosis and treatment of kratom use.