Kanna is a psychoactive plant, but it is not a controlled drug in the United States or most other countries. It’s sold legally as a dietary supplement. The plant, scientifically known as Sceletium tortuosum, contains alkaloids that affect serotonin activity in the brain, producing mood-lifting and anxiety-reducing effects. Whether you’d call it a “drug” depends on which definition you’re using: it’s pharmacologically active and mind-altering, but it’s not scheduled by the DEA or regulated like a prescription medication.
What Kanna Actually Is
Kanna is a succulent plant native to South Africa. Indigenous Khoisan peoples have chewed and smoked it for centuries as a mood elevator, pain reliever, anxiety reducer, and hunger suppressant. Traditional use also notes its intoxicating and euphoric effects at higher amounts.
The plant’s psychoactive properties come from a group of alkaloids, with the most important being mesembrine, mesembrenone, mesembrenol, mesembranol, and tortuosamine. These compounds are what separate kanna from an ordinary herbal tea. They cross into the brain and change how neurotransmitters behave, which is the same basic thing that pharmaceutical antidepressants do.
How It Works in the Brain
Kanna has long been described as a natural serotonin reuptake inhibitor, similar in concept to SSRI antidepressants. But research published in the Journal of Ethnopharmacology found the picture is more complex. High-mesembrine kanna extract actually functions primarily as a monoamine releasing agent, meaning it prompts brain cells to release more serotonin rather than simply preventing its reabsorption. The serotonin reuptake inhibition appears to be a secondary effect.
The extract also inhibits an enzyme called phosphodiesterase-4 (PDE4), which plays a role in inflammation and cognitive function. This dual action on both serotonin pathways and PDE4 is thought to explain why kanna seems to affect both mood and mental sharpness simultaneously.
What the Clinical Evidence Shows
The most rigorous human data comes from trials using Zembrin, a standardized kanna extract dosed at 25 mg per day. In a randomized, placebo-controlled trial on cognitively healthy adults, three weeks of supplementation significantly improved cognitive flexibility and executive function compared to placebo. The effect sizes were large: 1.47 for cognitive flexibility and 1.49 for executive function. Processing speed showed an even stronger effect size of 2.88, though not all domains improved equally (complex attention barely changed).
On the mood side, participants taking kanna reported improvements in irritability, anxiety, and drowsiness. Depression scores dropped by about 27% in the kanna group versus 14% with placebo, though that difference didn’t reach statistical significance due to high variability between participants. This was a small proof-of-concept study, so the cognitive findings are promising but far from definitive.
Legal and Regulatory Status
Kanna is not a scheduled substance under the DEA’s Controlled Substances Act. It is sold in the U.S. as a dietary supplement under the framework established by the Dietary Supplement Health and Education Act (DSHEA). Standardized extracts like Zembrin have gone through the FDA’s new dietary ingredient notification process, which requires manufacturers to demonstrate a reasonable expectation of safety, though not the same level of proof required for pharmaceutical drugs.
This means kanna occupies the same regulatory space as supplements like St. John’s wort or ashwagandha. You can buy it online or in supplement stores without a prescription. It is also unscheduled in most other countries, though regulations vary, and a few nations have placed restrictions on it.
How People Use It
Modern kanna products come in several forms: capsules containing standardized extract, loose powder, tinctures, and chewable tablets. Dosages in clinical trials have used 25 mg of standardized extract per day, which is a relatively small amount because the alkaloids are concentrated during extraction. Raw plant material requires much larger quantities to achieve similar effects.
Some people chew dried kanna plant material, brew it as tea, or use it sublingually (held under the tongue for faster absorption). Others smoke or insufflate the powder, which produces faster onset but also increases the intensity and unpredictability of effects. The route of administration matters significantly. Swallowing a low-dose standardized capsule produces a mild, subtle experience. Insufflating raw powder is a different situation entirely and carries more risk of side effects.
Risks and Interactions
At low, standardized doses, kanna appears to be well tolerated in clinical settings. However, there are real safety concerns that go beyond what you’d worry about with most supplements.
The most important risk involves combining kanna with anything else that raises serotonin levels. Because kanna both releases serotonin and inhibits its reuptake, stacking it with SSRI or SNRI antidepressants, MAOI inhibitors, or other serotonergic substances could theoretically push serotonin to dangerous levels, a condition called serotonin syndrome. Symptoms of serotonin syndrome range from agitation and rapid heartbeat to seizures in severe cases. If you take any psychiatric medication, this combination is not worth experimenting with.
Reported side effects from kanna itself tend to be mild at typical supplement doses: headache, nausea, and occasional digestive discomfort. At higher recreational doses, especially through insufflation, users report dizziness, increased heart rate, and uncomfortable overstimulation. There is limited data on long-term safety, and no well-established profile of dependence or withdrawal, though the traditional euphoric use suggests some potential for habituation at higher amounts.
Psychoactive but Not a Controlled Drug
Kanna genuinely alters brain chemistry. It releases serotonin, affects cognitive performance, reduces anxiety, and at sufficient doses produces euphoria. By any pharmacological definition, it is a psychoactive substance. But “drug” in the legal and regulatory sense means something specific, and kanna doesn’t meet that bar. It’s unscheduled, legal to purchase, and classified as a supplement. The distinction matters practically: no one will face legal consequences for buying or possessing it, but the lack of pharmaceutical-grade regulation also means product quality varies widely between brands, and what’s on the label may not match what’s in the bottle.