As clinicians and patients search urgently for alternatives to prescription opioids, kratom has emerged as one of the most contentious herbal candidates in the pain and addiction landscape, including in the realm of cancer care. Yet despite fervent advocacy from users who say it eases pain and helps them avoid opioids, regulators and many medical experts warn that kratom remains an unproven and potentially risky option for people living with cancer-related pain.
Kratom, derived from the leaves of the tropical tree Mitragyna speciosa, is native to Southeast Asia and has been used for centuries in countries such as Thailand and Malaysia for both medicinal and recreational purposes. The plant, a member of the coffee family, contains dozens of alkaloids, including mitragynine and 7-hydroxymitragynine, which interact with receptors in the brain and nervous system in complex ways that scientists are still working to fully understand.
At low doses, typically a few grams of powdered leaf, users commonly describe kratom’s effects as mildly euphoric and stimulating, with increases in energy and alertness that parallel, to some extent, the stimulant profile of caffeine. At higher doses, however, kratom takes on a very different character, acting more like a sedative and producing muscle relaxation, drowsiness and slower breathing, effects that stem from its activity at opioid receptors and resemble those of conventional opioid medications.
That dual profile has captured attention in oncology because cancer pain is both common and often complex, sometimes arising from the tumor itself, treatment-related nerve damage, inflammation or a mix of factors. The National Cancer Institute notes that cancer pain can significantly undermine quality of life and that opioids remain a mainstay for moderate to severe pain, especially in advanced disease, even as prescribers confront the wider public health crisis of opioid misuse and overdose. In this context, kratom’s ability to engage opioid receptors while remaining a plant-based, non-prescription product has made it attractive to some patients who are wary of traditional opioids or have experienced troubling side effects or dependence.
The CURE Today article “Considering Kratom as an Alternative to Opioids for Cancer-Related Pain” captures the collision of hope and uncertainty surrounding this herbal product. In interviews, emergency medicine clinical pharmacist Megan Rech describes what she sees in emergency departments: kratom users who passionately believe the plant eases their pain, lifts their mood and, crucially, helps them cut back on or avoid prescription opioids, alongside a growing number of patients experiencing serious complications after using unregulated kratom products.
Kratom’s supporters often point to self-report surveys in which users say they take the plant to manage chronic pain, improve mood and manage withdrawal symptoms from opioids or other substances, and in which many participants describe substantial relief. Some respondents report that kratom has allowed them to taper or stop opioid medications, and laboratory research has shown that key kratom alkaloids can bind to mu-opioid receptors, which could plausibly explain analgesic effects. For patients with cancer who struggle with side effects such as constipation, sedation or cognitive fog from prescribed opioids, the anecdotal accounts of more “functional” pain relief from an herbal product can be compelling.
However, those experiences, while important, do not substitute for rigorous clinical testing. Unlike FDA-approved medications for cancer pain or for opioid use disorder, kratom has not undergone randomized controlled trials to establish safe dosing, consistent efficacy or long-term safety, especially in medically fragile populations. The Food and Drug Administration, in a detailed advisory on “FDA and Kratom”, stresses that kratom is not approved as a drug, dietary supplement or food additive in the United States and warns that products containing kratom have been linked to serious adverse events, including liver toxicity, seizures and substance use disorder.
Regulatory history reflects that concern. In 2016, the Drug Enforcement Administration announced its intention to place kratom’s principal active compounds into Schedule I of the Controlled Substances Act, the same category as heroin and LSD, citing a high potential for abuse and no accepted medical use. After an intense backlash from kratom users, advocacy groups and some members of Congress, the agency took the unusual step of withdrawing its emergency scheduling notice later that year and has not completed a federal ban, leaving kratom in a legal gray zone in many jurisdictions, while some states and municipalities have independently prohibited its sale.
In parallel, federal public health agencies have escalated their warnings. The FDA has investigated kratom-related safety incidents over the past decade, reporting dozens of deaths in which kratom was present, typically alongside other substances, and reminding consumers that the absence of prescription status does not guarantee safety. The Centers for Disease Control and Prevention has similarly documented overdose deaths in which kratom was detected, emphasizing that the plant often appears in toxicology screens in combination with fentanyl, heroin, benzodiazepines or prescription opioids, making causality difficult to untangle but underscoring the risks when kratom is used within broader patterns of polysubstance use.
One of the most contentious points in the kratom debate is how to interpret these death reports. Advocates argue that dozens of deaths associated with kratom pale in comparison with the tens of thousands of annual fatalities involving prescription and illicit opioids, suggesting that kratom may represent a significantly safer option for some people. Regulators counter that the comparison is misleading because kratom has far less medical oversight and quality control, and that even a smaller number of serious adverse events is unacceptable for an unproven product marketed, often aggressively, as a natural solution for pain and addiction.
For patients with cancer, the stakes are particularly high. Cancer-related pain can be severe and constant, eroding sleep, appetite and mobility, and leading to anxiety and depression when inadequately controlled. Leading cancer organizations emphasize that when opioids are prescribed and monitored within a comprehensive pain management plan, they remain an essential tool for many patients, even as clinicians remain vigilant for signs of misuse or problematic side effects. Against this backdrop, some patients may understandably look to kratom as a way to regain a sense of autonomy or to avoid opioids altogether, especially if they have personal or family histories of addiction.
Megan Rech and other skeptics do not dispute the need for safer, more nuanced treatments for both pain and opioid dependence. What they question is whether kratom, in its current unregulated form, can fill that role responsibly. Without standardized manufacturing, kratom products can vary widely in potency and composition, and some have been found to be adulterated or contaminated. The FDA has issued import alerts and specific product warnings, including a 2024 advisory against a concentrated kratom extract after reports of serious health effects and at least one death, highlighting the dangers of highly potent formulations marketed online or in smoke shops.
From a clinical perspective, the lack of dosing guidelines poses additional problems. Physicians know how to titrate opioids like morphine or oxycodone in the context of cancer pain, adjusting doses based on renal and hepatic function, other medications and the trajectory of the disease. In contrast, patients who experiment with kratom typically rely on online forums or vendor recommendations, starting at doses that may seem modest but can accumulate over the day or interact unpredictably with chemotherapy agents, anti-nausea drugs, antidepressants or sedatives.
Another concern is the potential for dependence and withdrawal. While some people turn to kratom in hopes of easing withdrawal from opioids, there is growing recognition that kratom itself can lead to dependence, with users reporting cravings, tolerance and a withdrawal syndrome characterized by irritability, insomnia, muscle aches and gastrointestinal distress. Clinicians have begun to report cases in which patients require treatment for kratom use disorder, sometimes using buprenorphine-based therapies that are already established in the management of opioid dependence, blurring the line between “natural” remedy and yet another addictive substance.
In the CURE Today piece, Rech makes a pragmatic argument: until kratom is studied in robust, controlled trials and brought under a framework that ensures consistent quality and clear labeling, patients experiencing cancer-related pain or struggling with opioid dependence are better served with therapies that have undergone thorough evaluation. For opioid use disorder, those include medications such as methadone and the combination buprenorphine/naloxone, which have been extensively tested and are recommended by agencies like the Substance Abuse and Mental Health Services Administration as part of evidence-based treatment.
This does not mean that kratom should be dismissed outright as a research topic. On the contrary, many scientists argue that the plant’s complex pharmacology could yield novel compounds with analgesic or anti-addiction properties that carry lower risks of respiratory depression and overdose than conventional opioids, if they can be isolated, modified and rigorously tested. Some academic and government-funded teams are exploring kratom alkaloids as starting points for new drug development, but that long process bears little resemblance to the current retail market, where kratom is sold as powders, capsules and extracts with therapeutic claims that far outpace the data.
For now, the question facing patients with cancer is less about kratom’s theoretical potential than about immediate, practical decision-making. Pain specialists repeatedly urge patients not to self-medicate with kratom or other unregulated products without discussing them openly with their oncology and palliative care teams. Transparent conversations allow clinicians to identify possible drug interactions, monitor for side effects and consider whether any experimental use of kratom can occur within a broader strategy that includes established medications, physical therapies and psychological support.
As the United States continues to grapple with both an aging population and an entrenched opioid crisis, the pressure to find new tools for treating pain and addiction will only intensify. Kratom sits uncomfortably at the intersection of these needs, hailed by some as a lifeline and dismissed by others as a dangerous distraction from proven therapies. For people living with cancer, whose pain and vulnerability are all too real, the current evidence argues for caution: kratom may one day play a clearly defined role in pain management or opioid-sparing strategies, but today it remains a largely unregulated experiment that carries risks patients and clinicians must weigh carefully against better-understood options.