Kanna vs antidepressants
Kanna vs antidepressants: two different maps
If you take an antidepressant, don't add kanna, don't use it in place of your medicine, and don't stop or change your medicine without your prescriber.
One is a plant extract tested in a handful of small trials of healthy people. The other is a class of prescription medicines tested in hundreds of trials of people with depression. Here they are side by side.
- 8 small trials, healthy people
- Sold as a supplement
- Interactions never studied
- Hundreds of trials in depression
- Prescribed and monitored
- Interactions well documented
Map 1: ground kanna for sale in Cape Town; photo: Discott, CC BY‑SA 3.0, via Wikimedia Commons (cropped). Map 2: a plain blister pack, a drawing.
The short answer
Is kanna a natural alternative to antidepressants?
No. Antidepressants are prescription medicines tested in hundreds of trials of people with depression. Kanna is a plant extract tested in eight small trials of healthy volunteers, none with depression. Kanna's alkaloids touch the same serotonin target in lab dishes, which is a reason not to combine the two, not a reason to swap.
This page isn't a verdict on antidepressants or on kanna. It compares how much is known about each, how each is regulated and watched, and why we say never to mix them.
published human trials of kanna, all in healthy volunteers, the largest with 60 people.
trials, 116,477 adults with major depression, in one 2018 analysis of 21 antidepressants. All beat placebo (Cipriani 2018).
The evidence passport
Side by side, line by line
A plant extract sold as a dietary supplement.
Prescription medicines approved for depression, such as SSRIs.
8 small trials, 16 to 60 people each; 7 name one extract, Zembrin. Human trial
522 trials in one 2018 analysis alone (Cipriani 2018). Human trial
Never. All volunteers were healthy.
Yes: all 21 drugs analysed beat placebo for acute major depression in adults.
Serotonin transporter and PDE4 effects seen only in lab dishes. Bench
SSRIs block the serotonin transporter; that is what they were designed to do.
Sources: our census of kanna trials (How Kanna Works); Cipriani 2018; Boyer and Shannon 2005; Davies and Read 2019; Brendler 2021; KA! label.
The interaction line
Can you take kanna with an antidepressant?
No. Nobody has tested the combination, and kanna's alkaloids act on the serotonin system in lab tests, the same system these medicines act on.
- Seen in people
Nothing. No study has tested kanna with any medicine, and we found no published case report of a harmful interaction.
- Seen in the lab
Kanna extract blocked serotonin transporter binding (Harvey 2011), and a different extract changed transporter levels in cells in a way its authors read as serotonin release (Coetzee 2016).
- The concern
Too much serotonin activity, often from combining serotonergic drugs, causes serotonin syndrome, which can be serious (Boyer and Shannon 2005). We found no published case linked to kanna; the concern comes from how kanna acts.
- What reviewers say
A 2021 review advises against combining kanna with SSRIs and SNRIs (Brendler 2021). WebMD (reviewed March 2026) lists MAOIs, SSRIs, SNRIs, tricyclics, antipsychotics, triptans and St John's wort among medicines to discuss first.
- What KA! says
“Do not use KA! with SSRIs, MAOIs, SNRIs, NDRIs, Benzodiazepines or CNS depressants without medical supervision” (KA!'s label).
- Our position
Don't combine them. “Not studied” does not mean safe.
A label to retire
Is kanna “nature’s MDMA”?
What MDMA does
MDMA boosts the release of at least three brain messengers, serotonin, dopamine and norepinephrine, which drives its strong effects and its risks (NIDA).
It is a controlled drug in the US.
What kanna does
In lab dishes, kanna's alkaloids act on the serotonin transporter. No study has compared kanna with MDMA, and a 1996 review of 300 years of records found no evidence that kanna is hallucinogenic (Smith 1996).
The “natural MDMA” label comes from marketing and media, not research. KA! itself markets kanna as a “natural empathogen”. KA! says
If you take an antidepressant
Four things to know
- Don't add kanna
Not as chews, drops or capsules, and not “just a little”.
- Don't stop or switch on your own
Stopping an antidepressant suddenly can cause withdrawal effects, sometimes long lasting. Change only with your prescriber.
- If your medicine isn't working, say so
Your prescriber can adjust the dose, change the drug or add other support. Kanna is not one of the tested options.
- Tell your pharmacist about every supplement
Including kanna, St John's wort and 5‑HTP, which also act on serotonin.
In crisis or thinking about suicide? In the US, call or text 988 to reach the 988 Suicide & Crisis Lifeline. Elsewhere, contact your local emergency number.
Where KA! fits
A supplement, not a substitute
KA! sells kanna as a daily mood supplement, and its own label lists SSRIs, SNRIs, MAOIs and NDRIs among its contraindications. If you take none of the medicines on this page and want to read about the product, our KA! review covers the label, the cost per serving, the claims and, separately, my own experience with the products. If you decide to buy, code SAMA takes 15% off at KA!'s site. Our link applied code SAMA (15% off) by itself in our 9 Nov 2026 checkout test; if it is missing, enter SAMA before you pay. Affiliate link: we may earn a commission at no extra cost to you.
Quick answers
Kanna and antidepressants: questions
Can I take kanna with an SSRI?
No. The combination has never been studied, kanna's alkaloids act on the same serotonin target in lab tests, a 2021 review advises against it, and KA!'s own label lists SSRIs among its contraindications.
Can kanna replace my antidepressant?
No. Kanna has never been tested in people with depression. Don't stop or change a prescription without your prescriber.
Can kanna cause serotonin syndrome?
We found no published case. The concern comes from how kanna's alkaloids act in lab tests, which is why we say not to combine it with serotonergic medicines.
I stopped my antidepressant. When could I take kanna?
That depends on the medicine, and only your prescriber or pharmacist can tell you how long it stays active. If you stopped without your prescriber, tell them, because stopping can cause withdrawal effects. Kanna has not been tested as a treatment for depression.
What about anxiety medicines like benzodiazepines?
KA!'s label lists benzodiazepines and other CNS depressants in its contraindications, and KA! advises against alcohol. There are no human data either way, and one rat study found a kanna fraction caused loss of coordination. We would not combine them.
Is kanna an antidepressant?
No. It is a plant extract sold as a supplement. It is not approved to treat any condition, and it has not been tested as a treatment.
Map legend
Where to go next
Sources
What this page rests on
- Cipriani A et al. Comparative efficacy and acceptability of 21 antidepressant drugs. Lancet 2018. PubMed 29477251
- Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005. PubMed 15784664
- Davies J, Read J. A systematic review into the incidence, severity and duration of antidepressant withdrawal effects. Addict Behav 2019. PubMed 30292574
- Brendler T et al. Sceletium for managing anxiety, depression and cognitive impairment. Curr Neuropharmacol 2021. PMC8762184
- Harvey AL et al. 2011, PubMed 21798331; Coetzee DD et al. 2016, PubMed 26615766; Smith MT et al. 1996, PubMed 8691846.
- National Institute on Drug Abuse, MDMA (Ecstasy/Molly), read 9 Nov 2026.
- WebMD, Sceletium, medically reviewed 26 Mar 2026. KA! label and help center, read 9 Nov 2026.
- Loria MJ et al. Effects of Sceletium tortuosum in rats. J Ethnopharmacol 2014. PubMed 24930358
- Also cited on the earlier version of this page: Manganyi MC et al. 2021, PMC8124331 (review).
For educational purposes only. Nothing here is medical advice. Never start, stop or change a medicine without your prescriber. As an affiliate, samā·says may earn a commission on qualifying purchases made through links on this page.