What is Kanna?

Kanna, channa or kougoed is a chewable psychoactive substance made from a plant scientifically referred to as sceletium tortuosum.[1] Kougoed means something to chew on in Dutch or Afrikaans. The latin name reflects the fact that when dried, the veins give the plant a ‘skeletal’ appearance. It has a long history in South Africa of being used to alter someone's mood.[2] To prepare it for consumption it is traditionally crushed, then fermented, and dried after. The product is (like its name implies) preferably chewed but can be smoked, used to brew tea or eaten raw. To benefit from the psychoactive effects of kanna, it has to be fermented. This process combined with exposure to sunlight is required to obtain the active compounds including, but not limited to, mesembrine and delta-7-mesembrenone.[3]

Where does Kanna come from?

Sceletium tortuosum grows naturally in some parts of South Africa but can be cultivated anywhere under the right circumstances. It has been used for it’s cognitive effects by various tribes in what is now South Africa and has also been used in religious ceremonies by the San people. Due to its popularity it had been traded widely in and around the south of Africa. Kanna is available as a supplement, amongst others under the brand name Zembrin.

What are the effects of Kanna?

Even though there are studies on the mechanisms behind the supposed effects of kanna it is not fully understood yet. It is known that it has an effect on the serotonin system, inhibiting reuptake.[2] It also has a limited inhibition of noradrenaline and dopamine.[4][5] Furthermore some compounds in kanna may interact with the body’s cannabinoid system possibly leading to synergistic effects when combined with cannabis[6]. Kanna has also shown measurable beneficial effects when used to treat dementia,[8] cancer[2][4] and malaria.[9]


  • Reduced anxiety
  • Increased cognition [7]
  • Improved sleep
  • Reduced depression


How to use Kanna?

Kanna is available in various forms, as supplemental pills, finely ground plant material or even fermented and shredded plant material. There is evidence suggesting that the active compounds from kanna can enter the body more easily when it is chewed.[11] It is, however, not necessary to do so to experience the purported effects. Both powdered kanna and pills are widely available. Pills have the easiest way to dose but a limited ability to be finetuned. Powders can differ in strength and have to be adjusted accordingly.

How much Kanna to use?

When trying out new supplements it is wise to start with a lower dose and–depending on the experienced effects–increase or decrease the dosage accordingly

Kanna distributed under the brand name Zembrin comes in doses of 8 to 25 mg. One source compares it to 16 to 50 mg of dried plant material. Powders come in different strengths so it is not known what dosage to use to maximize effects.

What are the side effects of Kanna?

In a double blind study evaluating the side effects of kanna, 37 subjects taking 8 to 25 mg per day for 3 months showed no adverse effects compared to the control group. [12] There are no other known dangers or risks associated with the use of kanna.

Interactions of Kanna

Most nootropics are relatively safe to use on their own. Combining them with other substances may cause them to suddenly become dangerous or life-threatening.

As kanna has an effect on the serotonin system it may have harmful effects when combined with antidepressant drugs.


  1. [1] Smith, M. T., Field, C. R., Crouch, N. R., & Hirst, M. (1998). The Distribution of Mesembrine Alkaloids in Selected Taxa of the Mesembryanthemaceae and their Modification in the Sceletium Derived ‘Kougoed.’ Pharmaceutical Biology, 36(3), 173–179. https://doi.org/10.1076/phbi.
  2. [2] Gericke, N., & Viljoen, A. (2008). Sceletium—A review update. Journal of Ethnopharmacology, 119(3), 653–663. https://doi.org/10.1016/j.jep.2008.07.043
  3. [3] Patnala, S., & Kanfer, I. (2009). Investigations of the phytochemical content of Sceletium tortuosum following the preparation of 'Kougoed' by fermentation of plant material. Journal of Ethnopharmacology, 121(1), 86–91. https://doi.org/10.1016/j.jep.2008.10.008
  4. [4] Harvey, A. L., Young, L. C., Viljoen, A. M., & Gericke, N. P. (2011). Pharmacological actions of the South African medicinal and functional food plant Sceletium tortuosum and its principal alkaloids. Journal of Ethnopharmacology, 137(3), 1124–1129. https://doi.org/10.1016/j.jep.2011.07.035
  5. [5] Smith, C. (2011). The effects of Sceletium tortuosum in an in vivo model of psychological stress. Journal of Ethnopharmacology, 133(1), 31–36. https://doi.org/10.1016/j.jep.2010.08.058
  6. [6] Ho, C., Juliani, R. H., & Simon, J. (2010). African Natural Plant Products: New Discoveries and Challenges In Chemistry and Quality (1st ed.). American Chemical Society.
  7. [7] Dimpfel, W., Schombert, L., & Gericke, N. (2016). Electropharmacogram of Sceletium tortuosum extract based on spectral local field power in conscious freely moving rats. Journal of Ethnopharmacology, 177, 140–147. https://doi.org/10.1016/j.jep.2015.11.036
  8. [8] Chiu, S., Gericke, N., Farina-Woodbury, M., Badmaev, V., Raheb, H., Terpstra, K., Antongiorgi, J., Bureau, Y., Cernovsky, Z., Hou, J., Sanchez, V., Williams, M., Copen, J., Husni, M., & Goble, L. (2014). Proof-of-Concept Randomized Controlled Study of Cognition Effects of the Proprietary ExtractSceletium tortuosum(Zembrin) Targeting Phosphodiesterase-4 in Cognitively Healthy Subjects: Implications for Alzheimer’s Dementia. Evidence-Based Complementary and Alternative Medicine, 2014, 1–9. https://doi.org/10.1155/2014/682014
  9. [9] Setshedi, I. I., Fouche, G., Dewar, J., Maharaj, V., & Myer, M. S. (2012). Phytochemical isolation of compounds from Sceletium tortuosum and activity testing against Plasmodium falciparum. Onderstepoort J Vet Res, 79(2). https://doi.org/10.4102/ojvr.v79i2.481
  10. [10] Loria, M. J., Ali, Z., Abe, N., Sufka, K. J., & Khan, I. A. (2014). Effects of Sceletium tortuosum in rats. Journal of Ethnopharmacology, 155(1), 731–735. https://doi.org/10.1016/j.jep.2014.06.007
  11. [11] Shikanga, E., Viljoen, A., Chen, W., Hamman, J., Combrinck, S., & Gericke, N. (2011). An investigation of the in vitro transport of Sceletium tortuosum alkaloids across porcine buccal, sublingual and intestinal membranes. Planta Medica, 77(12). https://doi.org/10.1055/s-0031-1282478
  12. [12] Nell, H., Siebert, M., Chellan, P., & Gericke, N. (2013). A Randomized, Double-Blind, Parallel-Group, Placebo-Controlled Trial of Extract Sceletium tortuosum (Zembrin) in Healthy Adults. The Journal of Alternative and Complementary Medicine, 19(11), 898–904. https://doi.org/10.1089/acm.2012.0185
Other namesSceletium Tortuosum, channa, kougoed