Kratom produces effects similar to both opioids and stimulants, depending on how much you take. At low doses (1 to 5 grams of dried leaf), it acts more like a mild stimulant, comparable to caffeine or coca leaf. At higher doses (10 to 25 grams), it behaves much more like a traditional opioid painkiller, producing sedation, euphoria, and pain relief that researchers have compared to codeine and morphine.
This dual nature is what makes kratom unusual and why a simple comparison to any single substance falls short. The plant contains dozens of active compounds, and the two most important ones act on your brain in meaningfully different ways.
How Kratom Works Like an Opioid
Kratom’s two primary alkaloids, mitragynine and 7-hydroxymitragynine, both bind to the same brain receptors that morphine, codeine, and heroin target. But they do so with very different strengths. Mitragynine, which makes up the bulk of kratom’s alkaloid content, has relatively weak binding at these receptors and actually acts as a blocker rather than an activator in lab studies. The second compound, 7-hydroxymitragynine, binds about nine times more strongly and partially activates the receptor, producing opioid-like effects.
In animal studies, the pain-relieving and cough-suppressing effects of mitragynine were comparable to codeine, while 7-hydroxymitragynine proved several times more potent than morphine when given orally. Inside the body, the picture gets more complex. Mitragynine is converted into 7-hydroxymitragynine through metabolism, which helps explain why kratom produces opioid-like effects in people even though its most abundant alkaloid is technically an opioid receptor blocker in a test tube.
The opioid similarity goes beyond just how it feels. Mice that developed tolerance to 7-hydroxymitragynine also showed tolerance to morphine, and the reverse was true as well. This bidirectional cross-tolerance, along with similar withdrawal patterns, strongly suggests that kratom and conventional opioids are working through the same underlying mechanisms. For practical purposes, this means regular kratom use can reduce the effectiveness of prescription opioid painkillers, and vice versa.
The Stimulant Side
At lower doses, kratom doesn’t feel like an opioid at all. Users report increased energy, alertness, and sociability, effects the European Union Drugs Agency describes as “cocaine-like” stimulation. This is a key distinction from drugs like morphine or oxycodone, which are sedating at virtually any dose. Kratom’s stimulant properties come from its interactions with receptors beyond the opioid system, including those involved in dopamine signaling.
This stimulant effect is one reason kratom has been used as a traditional work aid in Southeast Asia for centuries. Laborers chewed the fresh leaves to combat fatigue, much the way coca leaves have been used in South America. The comparison to caffeine or coca is most accurate at these lower doses, typically under 5 grams of dried leaf.
Different Strains, Different Comparisons
Kratom products are commonly marketed by “vein color,” and the reported effects vary enough that each type draws comparisons to different substances. Red strains are described as calming and pain-relieving, making them the most opioid-like in character. White and green strains lean more stimulating and energizing. Green strains occupy a middle ground, with users reporting both calming and pain-reducing effects alongside moderate energy.
It’s worth noting that these distinctions come largely from user reports and product marketing rather than rigorous chemical analysis. The actual alkaloid content can vary widely between batches regardless of the labeled color. Still, the pattern is consistent enough that if you’re trying to understand what kratom resembles, the answer depends partly on which product someone is using and how much they take.
How It Compares to Kava and Kanna
People searching for natural mood-lifters often encounter kratom alongside two other botanicals: kava and kanna. The three plants overlap in some effects but work through entirely different brain chemistry.
Kava produces relaxation and reduces anxiety primarily through a system unrelated to opioids. It doesn’t provide pain relief or stimulation the way kratom does, and its calming effects are more comparable to a mild sedative or a glass of wine. Kava doesn’t carry the same risk of opioid-like dependence.
Kanna (Sceletium tortuosum) works by influencing serotonin levels in the brain, functioning more like a mild antidepressant than an opioid. Its effects tend to be gentler: elevated mood, reduced stress, and improved sociability without the deeper sedation or pain relief that higher-dose kratom provides. Kanna is better suited for daytime use and social situations, while kratom’s stronger relaxing strains are sometimes used before sleep. If kanna is closer to a cup of green tea with mood-lifting properties, high-dose red kratom is closer to a prescription painkiller in terms of the experience it produces.
Withdrawal and Dependence
Because kratom activates the same receptors as traditional opioids, regular use can lead to physical dependence. Withdrawal symptoms mirror those of opioid withdrawal: sweating, nausea, agitation, anxiety, and flu-like body aches. The severity generally tracks with how much and how long someone has been using.
This is another way kratom is fundamentally similar to opioids rather than to herbal supplements like kava or kanna. The cross-tolerance research makes this especially clear. Mice given 7-hydroxymitragynine long enough to become tolerant showed the same withdrawal signs seen with morphine dependence, and the mechanisms behind both appeared to be essentially the same.
Regulatory Status in the U.S.
Kratom occupies an unusual legal gray area. It is not a federally scheduled substance, meaning it’s legal at the national level, but as of January 2026, 30 states and the District of Columbia have enacted their own regulations. Some states have banned it outright, while others have passed consumer protection laws that regulate its sale without prohibiting it. The patchwork means legality depends entirely on where you live.
Adulteration is a real concern with unregulated kratom products. Products sold in Europe under names like “Krypton” were found to contain a metabolite of the synthetic opioid tramadol added to mimic kratom’s sedative effects, along with caffeine. This kind of spiking can dramatically increase the risk of overdose, particularly for someone who believes they’re taking a purely herbal product.
The Bottom Line on Comparisons
Kratom sits in a pharmacological space that doesn’t map neatly onto any single drug. At low doses, it’s closest to a mild stimulant like caffeine or coca leaf. At high doses, it behaves like a partial opioid, producing effects in the same family as codeine or tramadol but through a slightly different mechanism (partial activation rather than full activation of the opioid receptor). It carries real risks of tolerance, dependence, and withdrawal that are characteristic of opioids, not herbal supplements. And the unregulated market means the actual contents of any given product can vary significantly from what’s on the label.