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Ingredients/Herb/Kanna (Sceletium Tortuosum)

Kanna (Sceletium Tortuosum).

A traditional South African plant that naturally reduces anxiety and boosts mood by working on serotonin pathways. Reduces anxiety and elevates mood by inhibiting serotonin reuptake and blocking PDE4 (an enzyme linked to anxiety and inflammation)

PromisingResearch strength25 to 50mgDaily amount

Reviewed March 2026

KSHerb
Kanna (Sceletium Tortuosum)IngredientMD
Category
Herb

Also filed under
Anxiety and stress reductionMood elevationCognitive flexibility improvementFast onset (within hours)

What Kanna (Sceletium Tortuosum) is, and what it does.

Does it work
Suits people who want a daytime calm they can actually feel, and who can get a standardised extract. Anyone on a serotonergic prescription should clear it first.
How much to take
Start with 25mg of a standardised extract. The 25 to 50mg band is where the alkaloids do their work. Unstandardised plant material cannot be matched to it by weight.
Time to feel it
Most people notice something 30 to 60 minutes after a dose, and it eases off over the next few hours. The small trials on mood measures ran four to twelve weeks.
The first dose
A settled, unhurried feeling usually turns up inside the first hour and holds for several hours. This is one of the few plant extracts where day one is noticeable.
With regular use
Across weeks the day-to-day effect stays roughly steady. The four to twelve week trials tracked mood and stress questionnaire scores rather than sensations.
How well tolerated
Well tolerated in small trials at 25 to 50mg. Do not combine it with serotonergic prescription medicines, and speak to your prescriber before using it with any psychiatric medication.
How it feels
Quiet rather than sedating. The edge comes off while you stay alert, which is why it tends to be a daytime thing. A few people find it mildly stimulating instead.
The overlooked benefit
The fermentation step is chemistry, not just tradition. It shifts part of the mesembrine fraction toward mesembrenone, so fermented and unfermented material differ.

25 to 50mg a day is where Kanna (Sceletium Tortuosum) works.

How much to take a dayMedium confidence
Up to 25mgA supporting role. Common in blends where this is one active among several.
25 to 50mg
Daily maintenanceThe everyday amount, and where most daily supplements sit. This is the one you take month after month.
100mgClinical territory. Trials run high on purpose, for a set number of weeks, against one measured outcome. Impressive to hit, and not what a daily product is for.
Above 200mgPast what the research covers. More capsules rather than more effect.
MORE EFFECT ↑025mg100mg plateauDAILY DOSE →
The shaded band is where the dosing trials landed.

Source: Terburg et al. 2013, Nell et al. 2013 (Zembrin studies)

The proof, claim by claim.

These words describe the research, not the molecule's worth. Research strength is how much work stands behind one claim, and it is never a product score.

  • Reduces anxiety
  • Works as a natural SSRI
  • Elevates mood without sedation
PubMedCochraneClinicalTrials.govNIH ODSSUPP.AILabs test. IngredientMD verifies.PubMedCochraneClinicalTrials.govNIH ODSSUPP.AILabs test. IngredientMD verifies.

Questions people ask about Kanna (Sceletium Tortuosum).

Can I take this with my SSRI?
No. Absolutely not. Kanna works on the same serotonin system as SSRIs (Zoloft, Lexapro, Prozac, etc.). Combining them can cause serotonin syndrome: dangerously high serotonin levels leading to fever, seizures, and potentially death. If you're on an SSRI, kanna is off-limits. Talk to your doctor about alternatives.
Is this legal?
Yes, in the US, UK, and most countries. It's sold as a dietary supplement. However, it's a controlled substance in Louisiana and some other jurisdictions have considered restrictions. Check your local laws if you're outside the US.
How does it compare to ashwagandha for anxiety?
Different mechanisms, different timelines. Ashwagandha works through cortisol modulation and takes 4-8 weeks to build effects. Kanna works through serotonin and PDE4 inhibition and you feel it within an hour. For acute anxiety relief, kanna is faster. For chronic stress management, ashwagandha has more evidence. They can be combined safely.
Will I build tolerance?
Possibly, especially at higher doses used daily. The anxiolytic effects seem fairly tolerance-resistant at 25mg. The mood-elevating/euphoric effects (at higher doses) can diminish with daily use. Cycling helps: take 2 days off per week, or take a full week off every month.
Is fermented kanna better than unfermented?
Traditionally, yes. Fermentation changes the alkaloid profile, reducing oxalic acid and increasing mesembrenone (which contributes to the calm feeling). Unfermented kanna may have a more stimulating and less anxiolytic profile. The Zembrin extract sidesteps this question by standardizing the alkaloid ratios directly.
Pairs well with25 on file

Why these belong in the same formula. Each row says what the basis is, from settled biochemistry through to a trial that measured the pair.

Kanna (Sceletium Tortuosum) + 5-HTPadditive serotonergic load

Mesembrine is a serotonin reuptake inhibitor, so it raises synaptic serotonin, while 5-HTP raises the precursor pool feeding synthesis of that same transmitter. Supplying more substrate while slowing clearance stacks two steps of one pathway.

Tryptophan is the upstream precursor for serotonin synthesis and kanna slows serotonin reuptake at the transporter. The combination raises the same transmitter from both the production and the clearance side.

Hyperforin reduces monoamine reuptake by a different route to mesembrine, but the net effect at the synapse is the same transmitter rising. Two reuptake-slowing botanicals in one formula are additive.

SAM-e is the methyl donor supporting monoamine synthesis and turnover, and kanna slows serotonin reuptake. Both raise monoamine tone through different steps.

Theanine shifts cortical alpha activity and modulates glutamate receptor signalling, a different route to calm than the serotonergic and PDE4 actions of mesembrine. The two produce composure without stacking the same receptor.

Magnesium sits in the NMDA receptor channel and dampens excitatory glutamate signalling, while glycine itself is an inhibitory transmitter. Neither route overlaps with kanna's monoamine action, so the calming effects are complementary rather than duplicated.

Mesembrine inhibits phosphodiesterase 4, which raises cyclic AMP, and caffeine raises cyclic AMP by the same broad mechanism on top of adenosine receptor blockade. Stacking them amplifies alertness and the accompanying jitter.

Rhodiola constituents slow monoamine oxidase activity while kanna slows serotonin reuptake, so the transmitter is both broken down slower and cleared slower. Two monoamine-raising botanicals in one blend act additively.

Crocin and safranal are reported to modulate serotonin reuptake, the same transporter mesembrine acts on. Formulating both means one target is hit twice.

Kanna (Sceletium Tortuosum) + L-tyrosineEstablished biochemistry: tyrosine is the precursor for dopamine and noradrenaline, monoamines that overlap with the transporter targets described for Sceletium alkaloids in cell-based work.

Tyrosine supplies the substrate pool that tyrosine hydroxylase converts toward catecholamines. Mesembrine-type alkaloids have been characterised in vitro as monoamine transporter ligands, so the two touch the same neurotransmitter systems from different ends. No human combination study has been located and the pairing is proposed on biochemistry alone.

Kanna (Sceletium Tortuosum) + P5P (active B6)Established cofactor biochemistry: pyridoxal 5-phosphate is the cofactor for aromatic L-amino acid decarboxylase, the step that produces serotonin and dopamine.

Every monoamine neurotransmitter made from an aromatic amino acid passes through a decarboxylation step that requires pyridoxal 5-phosphate. Without adequate B6 status that step limits synthesis regardless of what else is in the formula. This is settled cofactor biochemistry and needs no trial to state.

Kanna (Sceletium Tortuosum) + Vitamin B6 (pyridoxine)Established cofactor biochemistry, with the conversion step made explicit.

Pyridoxine must be phosphorylated and oxidised to pyridoxal 5-phosphate before it serves as a cofactor for monoamine synthesis. That conversion depends on riboflavin-derived FAD, which is why B6 and B2 status travel together. The cofactor role is the grounding here, not any effect attributed to Sceletium.

Kanna (Sceletium Tortuosum) + MethylfolateEstablished one-carbon biochemistry: folate supports the methylation cycle that regenerates SAM-e, the methyl donor for monoamine metabolism.

5-methyltetrahydrofolate donates a methyl group to homocysteine, regenerating methionine and downstream SAM-e. SAM-e is the methyl donor for catechol-O-methyltransferase and for other monoamine-handling enzymes. This is cycle biochemistry rather than a demonstrated pairing with Sceletium.

Kanna (Sceletium Tortuosum) + Vitamin B12Established one-carbon biochemistry: B12 is the cofactor for methionine synthase, the enzyme that uses the folate methyl group.

Methionine synthase requires methylcobalamin to transfer the methyl group from folate to homocysteine. Low B12 status traps folate in its methyl form and stalls the cycle. The relationship is with the methylation cycle, not with the plant.

Kanna (Sceletium Tortuosum) + MagnesiumEstablished biochemistry: magnesium is required by the ATP-dependent kinases and the SAM-e-forming reaction in monoamine-related metabolism, and it modulates NMDA receptor activity.

Magnesium is a cofactor for several hundred enzymes, including the kinases that activate B vitamins and methionine adenosyltransferase. It also sits in the NMDA receptor channel as a voltage-dependent block. Both are established roles that stand on their own and are not a claim about Sceletium.

Kanna (Sceletium Tortuosum) + Bacopa monnieriCommon co-formulation in preparations positioned around normal mood and mental calm. Both are alkaloid or saponin-bearing botanicals with in vitro neurochemical activity.

Bacosides and mesembrine-type alkaloids are chemically unrelated and have been described in separate preclinical literatures. The two appear together in the same formula category. No combination study has been located and this is recorded as a formulation convention.

Kanna (Sceletium Tortuosum) + Lemon balmTraditional co-use in calming preparations. Lemon balm's rosmarinic acid has been characterised as a GABA transaminase inhibitor in vitro.

Lemon balm acts on the GABAergic side while Sceletium alkaloids have been described at monoamine transporters, so the two touch different systems in a formula meant to support a calm state. Both grounding statements come from in vitro pharmacology rather than from human trials. Kanna is not sedating in the way lemon balm can be, which is the practical difference between them.

Kanna (Sceletium Tortuosum) + PassionflowerTraditional calming pairing. Passionflower flavonoids have been described as GABA-A modulators in cell-based work.

Passionflower contributes flavonoid GABA-A modulation, a route unrelated to monoamine transporters. Combining the two spreads a formula across two neurotransmitter systems. There is no human evidence for the combination, which is why this is recorded at an early confidence.

Kanna (Sceletium Tortuosum) + ChamomileTraditional calming pairing. Apigenin from chamomile binds benzodiazepine sites in vitro.

Chamomile's apigenin has been characterised as a ligand at benzodiazepine binding sites in cell-based assays. That is a different mechanism from anything described for Sceletium alkaloids. The pairing is customary in calming blends and carries no combination data.

Kanna (Sceletium Tortuosum) + ApigeninEstablished in vitro pharmacology of the isolated flavone at benzodiazepine binding sites.

Apigenin as an isolated flavone acts on the GABA-A benzodiazepine site in cell-based work, quite separately from monoamine transporter activity. In an evening formula the two contribute different mechanisms. Kanna is generally used for daytime calm rather than for sleep, so the intended time of use differs.

Kanna (Sceletium Tortuosum) + Valerian rootAdditive calming effect worth flagging: valerian is sedating in a way Sceletium preparations generally are not.

Valerian constituents act on GABAergic signalling and can produce noticeable drowsiness. Stacking it with any other calming botanical increases the chance of daytime sedation, and the combination is worth flagging rather than recommending. This row is a caution about additive effect, not a benefit claim.

Kanna (Sceletium Tortuosum) + GABACommon co-formulation. The two act on different neurotransmitter systems.

Supplemental GABA crosses the blood brain barrier poorly, which is a well-known limitation of the ingredient, and its effects are often attributed to peripheral receptors. Sceletium alkaloids have been described at central monoamine transporters in vitro. The two are combined by convention and there is no interaction data.

Kanna (Sceletium Tortuosum) + AshwagandhaCommon adaptogen and calming pairing. Withanolides and mesembrine-type alkaloids are unrelated chemically.

Ashwagandha is described in the literature as acting on the hypothalamic pituitary adrenal axis, whereas Sceletium alkaloids have been characterised at monoamine transporters. The two sit in the same category of formula and are frequently combined. No combination study has been located.

Kanna (Sceletium Tortuosum) + TaurineEstablished neurochemistry: taurine acts at glycine and GABA-A receptors and is abundant in nervous tissue.

Taurine has an inhibitory receptor profile distinct from monoamine handling. Formulas aimed at a calm daytime state often carry both. The receptor pharmacology is established. The pairing with Sceletium is not studied.

Kanna (Sceletium Tortuosum) + MelatoninTiming conflict worth flagging: melatonin is a sleep-onset signal while Sceletium preparations are generally used in the daytime.

Melatonin acts on MT1 and MT2 receptors to shift circadian timing rather than to sedate directly. Pairing it with a daytime-use botanical puts two opposing intentions in one formula. This row exists to flag the mismatch rather than to propose a benefit.

Who should be cautious

Talk to a doctor before taking Kanna (Sceletium Tortuosum) if any of these apply to you: Do NOT combine with SSRIs or MAOIs (serotonin syndrome risk), Can cause nausea at high doses, Variable quality in non-standardized extracts. These are flags to check first, not effects Kanna (Sceletium Tortuosum) is known to cause.

Not medical advice. Show the label to your pharmacist.

What Kanna (Sceletium Tortuosum) actually does.

Established

Kanna carries mesembrine-type alkaloids: mesembrine, mesembrenone, mesembrenol and mesembranol. The ratio between them is what gives any given preparation its alkaloid fingerprint.

Established

How much alkaloid sits in kanna material swings with chemotype, plant part, harvest timing and the fermentation step. That's why a preparation gets specified by assayed alkaloid percentage rather than by plant weight.

Established

Alkaloids get counted by HPLC or LC-MS against reference standards, because a total-alkaloid titration can't tell the individual mesembrine-type alkaloids apart.

Established

Serotonin is built from tryptophan in two enzyme steps, and the second one needs the active form of B6, pyridoxal 5-phosphate. That puts B6 status upstream of any serotonergic formula.

Grown, 7 steps on record

Where Kanna (Sceletium Tortuosum) comes from.

The succulent is harvested and fermented, a step that traditionally happened in sealed animal hide bags and now happens in monitored vessels. That fermentation changes the plant's own chemistry, and only then is it dried and extracted.

Made from a plant. What ends up in the capsule tracks the harvest, so batch testing and a stated marker matter more here than with a made molecule.

Starts as
Sceletium tortuosum aerial parts

A succulent native to the Western and Northern Cape of South Africa, now largely cultivated rather than wild-harvested. The plant is protected material and its trade sits under access and benefit-sharing arrangements.

Converted by
Fermentation of the harvested plant

Harvested material is crushed and fermented, traditionally sealed in animal hide bags and now in controlled vessels with monitored temperature and time. The step changes the alkaloid profile rather than simply preserving the plant.

Converted by
Drying and milling

Fermented material is dried and milled to a powder that is either sold as raw material or carried forward for extraction.

Extracted by
Solvent extraction of the alkaloid fraction

Milled material is extracted with water, ethanol or a hydroalcoholic mixture to bring the alkaloids into solution, then filtered.

Purified by
Concentration and drying

The filtrate is concentrated under reduced pressure and dried, commonly onto a carrier, to give a stable powdered extract.

Standardised to
HPLC alkaloid assay

Batches are assayed by HPLC or LC-MS against reference standards for mesembrine, mesembrenone and related alkaloids, giving both a total figure and the ratio between them.

Ends up as
Capsule, tablet, powder or tincture

The dried extract is blended and encapsulated or tabletted. The hydroalcoholic extract may instead be filled as a liquid.

Whether material was fermented, and for how long, is often absent from a label even though it changes the alkaloid profile.

Getting Kanna (Sceletium Tortuosum) from food.

The whole-food sources on file. A supplement closes the gap, it does not replace dinner.

No food sourcesKanna tea

A gram-for-gram figure (how much of each you would eat to match a dose) will appear here once it is sourced and reviewed. This page will not print a number it cannot cite.

The forms it comes in.

Fermented dried plant materialWhole aerial parts fermented and dried, carrying the full alkaloid profile as the fermentation left it along with the rest of the plant matrix.Fits Preparations following the traditional method, where the whole fermented material is the intended ingredient.Trade-off Alkaloid content is not controlled unless the batch is assayed, so dose per gram varies between lots.
Standardised alkaloid extractAn extract specified against a total mesembrine-type alkaloid percentage confirmed by HPLC, with the individual alkaloid ratio also declared in some specifications.Fits Formulas that need a declared alkaloid amount rather than a plant weight.Trade-off Standardising to a total figure can hide a shifted ratio between individual alkaloids, so the profile matters as much as the total.
What the strongest studies found

The essence, in one line each.

  1. A review of the traditional and modern human evidence found only a small number of short trials of standardised Sceletium extract reporting changes in mood ratings and cognitive test performance in healthy adults, and the authors described the overall body of evidence as limited.Systematic review. Brendler et al., 2021 (Current neuropharmacology). PMID 33588735
  2. A bibliometric review of the Sceletium tortuosum literature maps research activity onto its phytochemistry and pharmacological activities, and shows the field is concentrated on mesembrine-type alkaloid characterisation rather than on human outcome studies.Narrative review. Reddy K et al., 2024 (Frontiers in Plant Science). PMID 38576783

These are the studies our verdict leans on, chosen from the 2 we read for Kanna (Sceletium Tortuosum). The full linked list is below.

FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This information is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement regimen.

On the shelf

What Kanna (Sceletium Tortuosum) comes in.

Products in our catalog that carry it, read the same way every product here is read.