Herb Profile
Kanna
Mesembryanthemum tortuosum
Kanna (Mesembryanthemum tortuosum) carries a Grade C rating — limited evidence.
Last reviewed: •3 sources citedReport a correctionProfile-wide ·C Limited
Use extra caution — CNS active and potentially serotonergic. Details
- Evidence
- Limited Evidence
- Typical onset
- Varies by prep
- Safety rating
- High caution
- Best for
- Mood Support, Anti Anxiety, Empathogen, Stress
- Avoid / review if
- Pregnancy/Breastfeeding, Bipolar/Mania Risk, Serotonin Syndrome Risk
Safety
Safety & Cautions
CNS active and potentially serotonergic. Avoid casual stacking with antidepressants or empathogenic/stimulant products.
High caution
Caution level: High. Multiple caution categories apply, or the record uses avoid/contraindication language.
- Interaction-AwareMedication or interaction context is explicitly noted.
- Stimulant-Like ProfileStimulant-like or activating caution language is present.
- Pregnancy/Breastfeeding CautionPregnancy or breastfeeding caution language is present.
Detailed safety fields
Pregnancy, breastfeeding, and contraindications
- Pregnancy/Breastfeeding
- Bipolar/Mania Risk
- Serotonin Syndrome Risk
- Active Psychiatric Medication Use Without Clinician Oversight.
- Avoid Or Clinician Review With SSRIs
- SNRIs
- MAOIs
- TCAs
- Lithium
- Tramadol
Safety classifications
- Interaction-Aware: Medication or interaction context is explicitly noted.
- Stimulant-Like Profile: Stimulant-like or activating caution language is present.
- Pregnancy/Breastfeeding Caution: Pregnancy or breastfeeding caution language is present.
Full safety note
- CNS active and potentially serotonergic. Avoid casual stacking with antidepressants or empathogenic/stimulant products.
Safety labels
- Interaction-Aware
- Stimulant-Like Profile
- Pregnancy/Breastfeeding Caution
Evidence-based safety
Caution when combined
Severity and certainty are shown separately. A high-priority caution can still be theoretical: these pairings are screened from shared contraindication mechanisms and are not automatically documented clinical interactions. Provenance identifies the source fields that produced each flag; it does not upgrade the certainty of the pairwise claim.
High-Priority Caution
26 flagged pairingsSerotonergic activity
High-Priority Caution
26 flagged pairingsSerotonergic activity
Representative pairings are shown below. Large mechanism groups are intentionally summarized to keep profiles focused and crawl-efficient.
Serotonergic activityCertainty: Theoretical
Data provenance recorded for 26 of 26 pairings in this mechanism group.
- 5-HTP — Theoretical interaction certainty
- Caffeine — Theoretical interaction certainty
- crocetin — Theoretical interaction certainty
- crocin — Theoretical interaction certainty
- Crocus Sativus — Theoretical interaction certainty
- Damiana — Theoretical interaction certainty
- DMT — Theoretical interaction certainty
- Ginkgo — Theoretical interaction certainty
- Panax Red Ginseng — Theoretical interaction certainty
- Panax White Ginseng — Theoretical interaction certainty
- Harmaline — Theoretical interaction certainty
- Harmine — Theoretical interaction certainty
+14 more pairings share this mechanism. Use the Safety Checker to review a specific combination.
Evidence
Evidence Summary
Evidence lens
Read as directional context, not settled clinical proof.
LimitedLimited Evidence
Human clinical evidence: Present in source signals
Mechanistic / preclinical: Mechanism mapped — Neurotransmitter Modulation · Stress Response Modulation
Research maturity: Emerging research — Long Term Human Evidence May Be Limited.
Safety boundary: Safety note available — CNS active and potentially serotonergic.
This profile cites 3 human studies.
Study design details
Evidence Grade
Grade C: Limited Evidence
Evaluation of methodological rigor, population reach, and evidence alignment.
- Design Match
- Meta-analysis
- Risk of Bias
- Low
- Consistency
- Not assessed
Strongest recorded design is a meta-analysis, drawn from 4 recorded studies, 1 in people.
How evidence grades work
Each grade reflects the strength and consistency of published human evidence — not marketing claims. Grades are based on study count, design quality, effect size, consistency, and recency.
- Strong
- Multiple RCTs, consistent direction, adequate effect size
- Moderate
- Some RCTs or consistent observational data in humans
- Preliminary / Mixed
- Animal or in-vitro only, or conflicting human data
- Traditional / Theoretical
- Traditional use only; no controlled human trials
Clinical Study Summaries (6)1 human evidence source · 0 human trials · Participant totals not consistently reported · Consistency not yet classifiable
Filter by study class
Showing 6 of 6 studies.
What the evidence actually shows
This table contains 6 structured sources, including 1 human evidence source; 0 are human trials.
| Study | Design | N | Dose | Duration | Population | Outcome | Result & magnitude | Source |
|---|---|---|---|---|---|---|---|---|
Background | Meta-analysis Statistically combines results from multiple eligible studies; confidence still depends on the quality, consistency, and directness of those studies. | — | — | — | — | — | A 2023 systematic review and meta-analysis of four randomized Sceletium studies involving 117 participants did not find a significant pooled clinical anxiety difference versus control (RR 1.01, 95% CI 0.56 to 1.83). | DOI → |
A Chewable Cure "Kanna": Biological and Pharmaceutical Properties of Sceletium tortuosum Manganyi MC et al. · Molecules · 2021 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
Mesembrine alkaloids: Review of their occurrence, chemistry, and pharmacology Krstenansky JL et al. · J Ethnopharmacol · 2017 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
Mesembryanthemum tortuosum and Zembrin: mixed evidence review Background | Animal research Tests effects in non-human animals. Useful for hypotheses and safety signals, but results may not translate to people. | — | — | — | — | — | A 2025 critical review found mixed human evidence: small studies suggest possible anxiety/stress, cognitive, and mood signals, but outcomes are inconsistent and many studies use healthy volunteers rather than clinically relevant populations. Large, condition-specific trials are still needed. | DOI → |
Meyer GM et al. · Anal Bioanal Chem · 2015 Background | Other / unclear The study design is not yet classified clearly enough to infer its place in the evidence hierarchy. | — | — | — | — | — | — | PubMed → |
Background | Other / unclear The study design is not yet classified clearly enough to infer its place in the evidence hierarchy. | — | — | — | — | — | A small acute pharmaco-fMRI study in 16 healthy adults found changes in amygdala threat reactivity and connectivity after a single standardized Sceletium tortuosum extract exposure. | PubMed → |
Dosing & Timing
- No standardized dose
- Preparation specific; use standardized product label for Fermented aerial material and require source backed dosage review before therapeutic claims.
How Kanna works
Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.
Mechanism Pathway — How Kanna Works
CompoundTarget / ReceptorMechanismEffect / Outcome
Mechanisms & biological pathways (preclinical)
- Neurotransmitter Modulation
- Stress Response Modulation
Active Compounds
Key constituents studied in Kanna, with full pharmacology and safety profiles.
Compare related active botanicals
Explore botanicals with similar chemistry, effects, or safety considerations in the Botanical Activity Atlas.
Compare & Sourcing
Compare side-by-side tradeoffs or verify active marker guidelines.
Sourcing options
Kanna product picks
Recommendation status
Product recommendations are not shown for this profile because the current site safety and monetization policy does not permit them.
Product form & quality guidelines
When sourcing Kanna, verify the label for:
- Standardized extract: Confirm active content percentages on the supplement facts panel (e.g. standardized to specific marker compounds) rather than simple raw herb weights.
- Third-party testing: Look for independent purity labels (USP, NSF, ConsumerLab, or Eurofins) to ensure the product is free from heavy metals, solvents, and contaminants.
- Form bioavailability: Ensure the form matches evidence-supported configurations (e.g. standardized active extracts like bacosides, withanolides, or curcuminoids) for optimal onset and digestion tolerance.
Safety first · Harm reduction
This information is educational and not medical advice. Start low, avoid risky combinations, and consult a licensed clinician before making health decisions—especially if you use medications, have diagnosed conditions, or are pregnant/breastfeeding.
Learn how we evaluate confidence, safety, and intensity on the methodology page.
Founder & Head Researcher · Oak Ridge, TN · Last reviewed August 2026
Editorial Review
Checked against primary sources, cited evidence, and contraindication language before publication. Evidence claims, safety language, and affiliate modules are reviewed independently. Not personal medical advice.
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