Sceletium tortuosum

Sceletium tortuosum is a succulent herb commonly found in South Africa, which is also known as Kanna, Channa, Kougoed (Kauwgoed) - which literally means, 'chew(able) things/goodies' or 'something to chew'. The plant has been used by South African pastoralists and hunter-gatherers as a mood-altering substance from prehistoric times. The first known written account of the plant's use was in 1662 by van Riebeeck. The traditionally prepared dried sceletium was often chewed and the saliva swallowed, but it has also been made into gel caps, teas and tinctures. It has also been used as a snuff and smoked.

Effects
Sceletium is known to elevate mood and decrease anxiety, stress and tension. It has also been used as an appetite suppressant by shepherds walking long distances in arid areas. In intoxicating doses it can cause euphoria, initially with stimulation and later with sedation. Users also report increased personal insight, interpersonal ease and a meditative, grounded feeling without any perceptual dulling. Others have noted enhanced tactile and sexual response. High doses produce distinct inebriation and stimulation often followed by sedation. The plant is not considered hallucinogenic, contrary to some literature on the subject, and no severe adverse effects have been documented.

Pharmacology
S. tortuosum can cause significant mood-elevation and anxiolytic (anti-anxiety) action. In doses as low as 50 mg users have reported improvements in mood, decreased anxiety, relaxation and a sense of well-being. At higher dosages near 100 mg, kanna acts as a calming euphoriant and empathogen.

The alkaloids contained in S. tortuosum believed to possess psychoactivity include: mesembrine, mesembrenone, mesembrenol and tortuosamine. Mesembrine is a major alkaloid present in Sceletium tortuosum, which has been shown to be a potent serotonin reuptake inhibitor (more so than imipramine), and a PDE4-inhibitor (less so than rolipram).

Sceletium tortuosum contains about 1-1.5% total alkaloids. There is about 0.3% mesembrine in the leaves and 0.86% in the stems of the plant.

Interactions
Little is known about the interactions of S. tortuosum, although it should not be combined with SSRIs, MAOIs, cardiac or psychiatric medications. Headaches in conjunction with alcohol have been noted with kanna use. Some reports suggest a synergy with cannabis.