What Is Kanna?
A plain-English guide to the South African succulent behind a growing number of non-alcoholic drinks.
Kanna is the common name for Sceletium tortuosum, a succulent plant native to South Africa. The San and Khoikhoi peoples traditionally chewed or fermented it. Its main compounds are mesembrine-type alkaloids. In lab tests they act on the serotonin transporter and an enzyme called PDE4. Human research is small and mostly uses one branded extract.
What is kanna?
Kanna is a low-growing succulent called Sceletium tortuosum, native to South Africa. Older texts file it under the synonym Mesembryanthemum tortuosum [1]. It has thick, fleshy leaves, it grows in dry regions, and it has been used by people for a very long time.
Researchers have identified around 25 alkaloids in the genus, grouped into four chemical classes. The mesembrine class is the predominant one [1]. Those alkaloids are the reason scientists, and now drink makers, take an interest in the plant.
Kanna is not a new invention. What is new is the attention: standardized extracts, small human trials in the last decade or so, and a wave of consumer products. This page covers the plant, its history, what the research says about how it works, and where drinks fit in. For what the human studies actually found, read Kanna Benefits: What the Research Actually Shows.
What are kanna, kougoed and Zembrin?
All three words come up around the same plant, but they are not interchangeable.
| Name | What it means |
|---|---|
| Kanna | The common name for the plant, Sceletium tortuosum. |
| Kougoed | A name associated with the traditionally fermented, prepared plant material [3]. |
| Sceletium | The genus name. You will see it on supplement labels and in the research literature. |
| Zembrin | A trademarked, standardized kanna extract. Most published human trials used it [2][6][7][9]. |
The Zembrin point matters. When a study says "kanna improved X," read it as "this particular extract, at this dose, in these people." A cup of dried leaf, a tincture and a beverage extract can differ a great deal in alkaloid content. We come back to this in the dosage guide.
How have the San and Khoikhoi used kanna?
The San and Khoikhoi peoples of southern Africa have a long history of using kanna as a masticatory, meaning something chewed, and as a traditional medicine [2]. European colonial farmers later used it as a psychotropic in tincture form [2].
Review articles describe a range of traditional uses: lifting mood, easing pain, relieving toothache and abdominal pain, and suppressing thirst and hunger [1]. These are descriptions of traditional practice, not findings from modern trials, and we are not saying kanna does any of them.
The plant was traditionally chewed or smoked, and it was also fermented, which is the preparation linked to the word kougoed [3]. That history is worth stating plainly and respectfully. Knowledge about this plant comes from communities who used it for generations before laboratories studied it. Any modern product sits downstream of that.
What is in kanna?
The main active compounds are mesembrine-type alkaloids, including mesembrine, mesembrenone and mesembrenol [1]. The plant contains many other compounds, but the mesembrine group is the one researchers focus on.
Alkaloid content varies. It depends on the plant, how it was grown and processed, and how an extract was made. That variation is one reason standardized extracts exist, and it is why "50 mg of kanna" on one label can mean something quite different from 50 mg on another.
How is kanna thought to work?
In laboratory studies, kanna alkaloids block the serotonin transporter and inhibit an enzyme called phosphodiesterase-4 (PDE4). That is the leading explanation, and it is still a hypothesis rather than a settled mechanism.
In a 2011 lab study, a standardized extract blocked the serotonin transporter (IC50 4.3 ug/ml) and inhibited PDE4 (IC50 8.5 ug/ml). Mesembrine was the most potent alkaloid at the serotonin transporter (Ki 1.4 nM), and mesembrenone acted on both targets [4]. The serotonin transporter is the protein that clears serotonin from the gap between nerve cells. PDE4 is involved in breaking down a signaling molecule inside cells.
There is a caveat. A 2016 cell study of a high-mesembrine extract argued that serotonin reuptake inhibition may be secondary to a monoamine-releasing effect [5]. In other words, even the basic mechanism is being debated. Cell studies also do not tell you what happens in a person drinking a can of soda.
One brain imaging study gives a loose hint of effects in people. In 16 healthy volunteers, a single 25 mg dose of Zembrin reduced amygdala reactivity to fearful faces under one test condition, and reduced coupling between the amygdala and hypothalamus [2]. It was a small, placebo-controlled crossover trial. It shows a measurable brain response, not a health benefit.
What does kanna feel like in studies?
The studies measure things like test performance and self-reported ratings, and the results are modest and mixed. No trial describes a dramatic "kanna feeling," and we are not going to invent one.
- In a 3-week trial of 21 healthy adults (mean age 54.6), 25 mg per day of Zembrin was associated with better cognitive set flexibility and executive function than placebo. The authors also reported positive changes in mood and sleep, and the extract was well tolerated [6].
- In two small studies totaling 20 young, healthy volunteers, a single 25 mg dose had no effect during a multitasking stressor. In a simulated public-speaking task, it was associated with lower self-reported anxiety beforehand and a significant treatment-by-time effect on heart rate. The authors called it "first tentative behavioral evidence" [7].
- In 60 recreationally trained adults taking 25 mg for 8 days, performance on a complex reactive task under cognitive load improved, but mood scores and alertness ratings did not change [8].
- In a 3-month safety trial of 37 people, 8 mg or 25 mg of Zembrin daily produced no differences in vital signs, ECG or bloodwork. Headache was the most common side effect, and it was more frequent on placebo. Efficacy was not assessed [9].
The honest summary: small studies, healthy people, one extract, and some outcomes that did not move. A 2026 critical review of animal and clinical studies found a favourable safety profile and potential efficacy, but described the evidence as mixed and limited by small sample sizes [10]. Our benefits page goes through each study in a table.
What forms does kanna come in?
Kanna is sold as a chewed or fermented plant material, a tincture, a standardized extract, and in newer consumer formats such as chews, melts and drinks.
| Form | Notes |
|---|---|
| Chewed or fermented plant material | The traditional route. Chewed, and also smoked, according to the pharmacognosy literature [3]. |
| Tincture | How European colonial farmers used it [2]. |
| Standardized extract | What clinical trials use. Zembrin is the best-known example [6][9]. |
| Chews and melts | Consumer products sold at roughly 10 to 30 mg of kanna per piece, per one retail roundup [11]. |
| Drinks and shots | Canned sodas, spritzes and 2 oz shots. Kanna per serving ranges widely across brands. |
We have not found a trustworthy source on kanna tea strengths, so we are not making claims about it.
Why is kanna showing up in non-alcoholic drinks?
Mostly because the non-alcoholic category is looking for ingredients that give a drink something to do beyond tasting good, and kanna is a recognizable plant with a published research record. That is our read, not a scientific finding.
Brand launches in 2026 point the same way. On the Brightside, for example, launched a zero-sugar, zero-alcohol kanna soda in July 2026 [12]. Other brands pair kanna with kava, L-theanine or lion's mane. Silly, the kanna and lion's mane drink from Psilly Goose, the publisher of this site, is one of them; see our ranking for how it compares.
The catch is that drinks vary a lot. Cans on the market range from 15 mg to 500 mg of kanna, using different extracts that are not directly comparable. Published human trials have used 8 mg to 50 mg per day of Zembrin, most often 25 mg. See how much kanna is in a drink for a side-by-side table.
What should you know before trying it?
Talk to a doctor or pharmacist first if you take any serotonergic medicine, and skip kanna if you are pregnant or nursing unless a clinician says otherwise.
- Medicine interactions. Interaction concerns have been raised with MAOIs, SSRIs, SNRIs, tricyclic antidepressants, antipsychotics, triptans and St. John's wort. How these interactions play out is not fully understood [13].
- Pregnancy and nursing. There are no data on safety during pregnancy or breastfeeding [13].
- Regulatory status. The FDA has not reviewed sceletium for safety and effectiveness, and product content can vary [13]. Rules differ by country [14].
- Side effects. Headache and upset stomach are the commonly reported ones [13].
For more detail, see Is Kanna Safe? and Is Kanna Legal?. Nothing on this page is medical advice, and kanna products are not intended for the diagnosis, prevention or management of any disease.
References
- Olatunji TL et al. Sceletium tortuosum: a review on its phytochemistry, pharmacokinetics, biological and clinical activities. J Ethnopharmacol 2021;280:114476. PubMed
- Terburg D et al. Acute effects of Sceletium tortuosum (Zembrin), a dual 5-HT reuptake and PDE4 inhibitor, in the human amygdala and its connection to the hypothalamus. Neuropsychopharmacology 2013;38(13):2708-16. PubMed
- Patnala S, Kanfer I. Investigations of the phytochemical content of Sceletium tortuosum following the preparation of "Kougoed" by fermentation of plant material. J Ethnopharmacol 2009;121:86-91. PubMed
- Harvey AL et al. Pharmacological actions of the South African medicinal and functional food plant Sceletium tortuosum and its principal alkaloids. J Ethnopharmacol 2011;137(3):1124-9. PubMed
- Coetzee DD et al. High-mesembrine Sceletium extract (Trimesemine) is a monoamine releasing agent, rather than only a selective serotonin reuptake inhibitor. J Ethnopharmacol 2016;177:111-6. PubMed
- Chiu S et al. Proof-of-concept randomized controlled study of cognition effects of the proprietary extract Sceletium tortuosum (Zembrin) targeting phosphodiesterase-4 in cognitively healthy subjects. Evid Based Complement Alternat Med 2014;2014:682014. PubMed
- Reay J et al. Sceletium tortuosum (Zembrin) ameliorates experimentally induced anxiety in healthy volunteers. Hum Psychopharmacol 2020;35(6):1-7. PubMed
- Hoffman JR et al. Ergogenic effects of 8 days of Sceletium tortuosum supplementation on mood, visual tracking, and reaction in recreationally trained men and women. J Strength Cond Res 2020;34(9):2476-81. PubMed
- Nell H et al. A randomized, double-blind, parallel-group, placebo-controlled trial of extract Sceletium tortuosum (Zembrin) in healthy adults. J Altern Complement Med 2013;19(11):898-904. PubMed
- de Jong M et al. Mesembryanthemum tortuosum and Zembrin: mixed evidence from in vivo animal and clinical studies on their antidepressant and anxiolytic effects. Planta Med 2026;92(8):806-823. PubMed
- GreenState. Best kanna products (retail roundup of chews, melts and tinctures). GreenState
- BevNET. Introducing On the Brightside, the feel-good soda (press release), July 8, 2026. BevNET
- WebMD. Sceletium: uses, side effects, interactions. WebMD
- Brendler T et al. Sceletium for managing anxiety, depression and cognitive impairment: a traditional herbal medicine in modern-day regulatory systems. Curr Neuropharmacol 2021;19(9):1384-1400. PubMed
Frequently asked questions
What is kanna?
Kanna is the common name for Sceletium tortuosum, a succulent plant native to South Africa. Its leaves and stems contain mesembrine-type alkaloids and have a long history of traditional use as a chewed or fermented plant material.
Is kanna the same as Zembrin?
No. Zembrin is a trademarked, standardized kanna extract used in most of the human studies. Kanna is the plant; Zembrin is one specific extract of it, so results from Zembrin trials do not automatically apply to other products.
Is kanna the same as kava?
No. They are unrelated plants with different active compounds. Kanna is a South African succulent; kava comes from a Pacific Island pepper plant. See our kanna vs kava comparison.
Does kanna have caffeine?
The plant itself does not contain caffeine. Some drinks add caffeine separately, so check each label.
Is kanna safe to combine with antidepressants?
Not without medical advice. Kanna may interact with serotonergic medicines such as SSRIs, SNRIs and MAOIs. Talk to a doctor or pharmacist first. More in our safety guide.