The rule in herbalism dictates that any herb use should be slow and gradual, so that any possible bad reaction will be minimized.

Kanna is traditionally used as a sedative in the form of a smoke, tea, decoction or tincture.

Kanna has been used by hunter-gatherers and shepherds as a mood-enhancing substance for millennia, and is far more effective and rapidly acting than the well-known European plant Hypericum (St John's Wort). Indications: Low mood, winter-blues, mood swings. Anxiety, stress, nervous tension. Alcoholic rehabilitation support. Irritability in smoking-cessation.

The genus Mesembryanthemum is a popular groundcover, traditional as a sacramental herb in South Africa. For hundreds of years the Hottentots used Sceletium expansum and tortuosum as a sacramental sedative and mood enhancer called Kanna or Channa (not Cannabis).

The Dutch, upon their arrival in Africa in the 1660's, called it 'Kougoed' (kauwgoed) which literally means, 'chew(able) things/goodies' or 'something to chew'.

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The National Institute of Mental Health in the United States have found Memembrine the principle alkaloid responsible for psychoactivity in Sceletium Tortuosum to be a serotonin-uptake inhibitor, keeping more serotonin in circulation, like Prozac. Since Prozac/SSRI's are contraindicated with MAOI, this would also go for Mesembrine. Also the results of taking it ontop of other SSRI's are unpredictable, and it is known that alcohol can also cause side effects combined with many SSRI's. Headaches in conjunction with alcohol have been noted with sceletium use.