Compound Monograph
Mesembrine
Mesembrine is the principal alkaloid of kanna (Sceletium tortuosum), studied mainly as a serotonin reuptake inhibitor.
Classification
Mesembrine is a mesembrine alkaloid, part of the alkaloids class. Nitrogen-containing, often bitter and physiologically potent compounds — the group behind many of the strongest plant medicines and poisons.
Where Does It Come From? (2)
Mesembrine is a naturally occurring mesembrine alkaloid, found in Kanna and Ice plant. It is flagged as moderately toxic.
Research & Evidence
Mesembrine is the best-known alkaloid of Sceletium tortuosum (kanna), a succulent traditionally used in southern Africa as a mood-altering and chewing herb. Pharmacologically it is most often described as a serotonin reuptake inhibitor, and it also shows phosphodiesterase-4 (PDE4) inhibition in laboratory assays. These mechanisms are the basis for interest in standardised kanna extracts for mood and anxiety, though rigorous human data remain limited.
Toxicity & Safety
The isolated alkaloid has not been extensively characterised in humans. Because of its serotonergic activity, caution is generally advised when combining kanna or mesembrine with antidepressants and other serotonergic drugs.