Compound or practice · Supplement
Kanna (Sceletium tortuosum)
A South African mood herb (standardized as Zembrin) with early anxiolytic and cognitive signals — and serotonergic caution.
- Overall grade
- Grade C
- Last revised
- 2
- graded outcomes
- 0
- references listed
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
2 at grade C — 2 graded rows
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Anxiety / moodEvidence grade C
Zembrin extract
Smallmixed
- Cognition (executive)Evidence grade C
Early
Smalllow
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Anxiety / mood (grade C); Cognition (executive) (grade C).
- Caution with SSRIs / SNRIs: SSRI-like reuptake inhibition — serotonin-syndrome risk; don't combine.
Interactions
Documented pairings with supplements and medicines. A medicine on this list is a conversation for whoever prescribes it.
SSRIs / SNRIsCaution
SSRI-like reuptake inhibition — serotonin-syndrome risk; don't combine.
The evidence in words
What it is
Kanna is a succulent traditionally chewed for mood; the standardized extract Zembrin is used for stress and cognition.
How it works
Its alkaloids (mesembrine) inhibit serotonin reuptake and PDE4, giving combined serotonergic and pro-cognitive effects.
What the evidence shows
Small trials of Zembrin show reduced anxiety, improved mood, and better executive function / amygdala reactivity. The evidence is early and the extract-specific; because it's an SSRI-like agent, it shouldn't be combined with antidepressants.
Safety & interactions
Generally tolerated (mild headache, GI); being serotonergic, do not combine with SSRIs/SNRIs/MAOIs — serotonin-syndrome risk. ssri — SSRI-like reuptake inhibition — serotonin-syndrome risk; don't combine.
Bottom line
A promising mood-and-focus herb with a real dual mechanism — but treat it like a serotonergic agent and never stack it with antidepressants.
Related reading
Entries that share this one's tags or conditions.
- Kanna (Sceletium tortuosum) for Anxiety / moodEvidence grade C — Zembrin extractEvidence grade C
- Kanna (Sceletium tortuosum) for Cognition (executive)Evidence grade C — EarlyEvidence grade C
- Kanna (Sceletium tortuosum): side effects, safety & interactionsGenerally tolerated (mild headache, GI); being serotonergic, do not combine with SSRIs/SNRIs/MAOIs — serotonin-syndrome Evidence grade C
- SaffronSurprisingly solid for low mood at ~30 mg/day — a rare botantical antidepressant with real trials, carrying the serotonergic caveat.Evidence grade B
Sources
This entry lists no references of its own.
Last revised . A grade is this entry's reading of the evidence, not medical advice.