Drug & supplement interaction

Sceletium + Phentermine

Phentermine brand names: Adipex-P, Fastin, T Diet, Phentride, Obenix, and others.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Sceletium and Phentermine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Sceletium and Phentermine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Phentermine and Sceletium in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Sceletium safety at a glance

Sceletium overall Use caution It appears generally tolerable in small studies, but long-term safety is not well established.
Pregnancy Avoid There is not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid Safety data are lacking, so avoid use while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Phentermine and Sceletium? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Phentermine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Phentermine is filed under 2 classifications — stimulant drugs, oral drugs. Sceletium has documented interactions with 1 drug class — the most serious being cns depressants (moderate) — and none of Phentermine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Sceletium Does Interact With Other Medications

Sceletium has 248 moderate known drug interactions in our database — Phentermine isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Sceletium

Covers the 2,830 medications we’ve checked against Sceletium. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Sceletium and Phentermine May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • Raised blood pressure Worth acting on Additional detail

    Sceletium

    “Orally, a sceletium extract has been reported to cause hypertension.”

    Sceletium · Natural Medicines adverse-effect record, reported in hypertension.

    1 source cited
    1. 106745. Gericke J, Lekhooa M, Steyn SF, Viljoen AM, Harvey BH. An acute dose-ranging evaluation of the antidepressant properties of Sceletium tortuosum (Zembrin®) versus escitalopram in the Flinders Sensitive Line rat. J Ethnopharmacol. 2022 Feb 10;284:114550. do PubMed

    Phentermine

    Listed in the ADVERSE REACTIONS section of the FDA label for Phentermine. Read the label on DailyMed ›

  • Anxiety or restlessness / Trouble sleeping / Headache Additional detail

    Sceletium

    “Orally, a sceletium extract has been reported to cause anxiety, headache, insomnia, and irritability. There are also anecdotal reports that chewing sceletium can cause headache, depression, and listlessness. Additionally, anecdotal reports suggest that sceletium can cause euphoric effects when inhaled or taken orally in high doses.”

    Sceletium · Natural Medicines adverse-effect record, reported in anxiety.

    3 sources cited
    1. 106745. Gericke J, Lekhooa M, Steyn SF, Viljoen AM, Harvey BH. An acute dose-ranging evaluation of the antidepressant properties of Sceletium tortuosum (Zembrin®) versus escitalopram in the Flinders Sensitive Line rat. J Ethnopharmacol. 2022 Feb 10;284:114550. do PubMed
    2. 17580. Smith MT, Crouch NR, Gericke N, Hirst M. Psychoactive constituents of the genus Sceletium N.E.Br. and other Mesembryanthemaceae: a review. J Ethnopharmacol 1996;50:119-30. PubMed
    3. 100649. Meyer GMJ, Wink CSD, Zapp J, Maurer HH. GC-MS, LC-MS(n), LC-high resolution-MS(n), and NMR studies on the metabolism and toxicological detection of mesembrine and mesembrenone, the main alkaloids of the legal high "Kanna" isolated from Sceletium tortuosum

    Phentermine

    Listed in the ADVERSE REACTIONS section of the FDA label for Phentermine. Read the label on DailyMed ›

Reported for Sceletium but not commonly for Phentermine: reduced appetite, mood changes or irritability, low mood and nausea.

Effects for Phentermine come from the ADVERSE REACTIONS section of its FDA label; effects for Sceletium come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Overlapping uses

What Phentermine Is Prescribed For, and What Sceletium Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Phentermine is a prescription medicine with approved uses on its FDA label. Sceletium is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Phentermine is prescribed for: Phentermine is approved as a short-term addition to a weight-loss program — not a standalone treatment. It is used alongside reduced-calorie eating, increased physical activity, and behavior changes to help manage obesity in adults whose body mass index (BMI) is 30 kg/m² or higher, or 27 kg/m² or higher when other risk factors such as controlled high blood pressure, diabetes, or high cholesterol (hyperlipidemia) are also present. All available phentermine products — including Adipex-P, Lomaira, and various generic capsules and tablets — share this same FDA-approved use. Lomaira tablets are specifically dosed to be taken three times daily before meals, while other formulations are generally taken once daily.

Read the rest of what Phentermine is prescribed for

Treatment is intended to last only a few weeks.

Sceletium has been studied for:

  • Obesity studied, not established Sceletium has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Sceletium for obesity

    Although there has been interest in using oral sceletium for obesity, there is insufficient reliable information about the clinical effects of sceletium for this purpose.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Phentermine on your own; if you are taking Sceletium for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Sceletium or Phentermine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Sceletium or Phentermine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Phentermine

This page covers Sceletium only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phentermine page lists 61 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Peyote (major), Rauvolfia Vomitoria (major) and Sida Cordifolia (major).

By severity: 5 major · 43 moderate · 13 minor.

From our pharmacist’s overview on the Phentermine page

“Ephedra is the pairing I most want anyone taking phentermine (Adipex-P) to know about. Phentermine is itself a stimulant appetite suppressant that raises heart rate and blood pressure, and ephedra piles the same cardiovascular strain on top of it.”

Reviewed by 2 · Jul 18, 2026

Open the Phentermine interaction page

One more smart check

Taking Sceletium as Part of a Dietary Supplement Product? Check It for Interactions

We hold 132 real supplement products containing Sceletium, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Sceletium. Even though Sceletium itself has no known interaction with Phentermine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Sceletium and Phentermine Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Sceletium
Top half

#412 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phentermine
Top 25%

#498 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Sceletium reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Sceletium and Phentermine records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Sceletium

What is Sceletium?

  • Anxiety and stress
  • Low mood
  • Mental focus and cognition
  • Relaxation
  • Traditional use as a mood lifter

Sceletium (often sold as 'kanna') is a South African plant traditionally used to ease stress and lift mood. Early human studies are small and short, so its benefits are not well proven. Talk to your pharmacist or doctor before trying it, and avoid it during pregnancy and breastfeeding.

Sceletium tortuosum · Aizoaceae · Aerial parts (leaves, stems, and flowers), often fermented · Capsules, tablets, powders, tinctures, chewed plant material, and tea

An interaction check asks whether these two react with each other — it does not ask whether Sceletium is a good idea for someone in your situation. Here is what our Sceletium record says about it on its own.

Sceletium: dosing

There is no official, well-established dose for Sceletium. Products differ greatly in their strength and in how they are prepared and standardized.If you choose to use it, follow the directions on the product label and do not exceed the suggested amount.

From our Sceletium monograph — the full record covers uses, side effects and every documented interaction.

Read the full Sceletium monograph & all interactions
Medication

About Phentermine

What Is Phentermine Used For?

Brand names: Adipex-P, Fastin, T Diet, Phentride, Obenix, Pbc Phentride, Pbw Phentride, Phentrol #3, Ionamin, Phentrol #6, Phentrol #2, Phentrol #5, Phentrol, Obermine, Phentermine, Suprenza

Phentermine is approved as a short-term addition to a weight-loss program — not a standalone treatment. It is used alongside reduced-calorie eating, increased physical activity, and behavior changes to help manage obesity in adults whose body mass index (BMI) is 30 kg/m² or higher, or 27 kg/m² or higher when other risk factors such as controlled high blood pressure, diabetes, or high cholesterol (hyperlipidemia) are also present.

All available phentermine products — including Adipex-P, Lomaira, and various generic capsules and tablets — share this same FDA-approved use. Lomaira tablets are specifically dosed to be taken three times daily before meals, while other formulations are generally taken once daily. Treatment is intended to last only a few weeks.

See full Phentermine drug information
Keep checking

Other Drugs & Sceletium

Browse every other medication we’ve checked against Sceletium — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
248Moderate
0Minor
2,581No known interaction
Moderate

248 interactions

Showing 60 of 248 moderate interactions — see all 248 on the Sceletium page.

No interaction 2,581 drugs checked — show the list
Evidence & sources

Sceletium References

The 3 references that drive our Sceletium monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Smith MT, Crouch NR, Gericke N, Hirst M. Psychoactive constituents of the genus Sceletium N.E.Br. and other Mesembryanthemaceae: a review. J Ethnopharmacol 1996;50:119-30. PubMed
  2. Meyer GMJ, Wink CSD, Zapp J, Maurer HH. GC-MS, LC-MS(n), LC-high resolution-MS(n), and NMR studies on the metabolism and toxicological detection of mesembrine and mesembrenone, the main alkaloids of the legal high "Kanna" isolated from Sceletium tortuosum
  3. Gericke J, Lekhooa M, Steyn SF, Viljoen AM, Harvey BH. An acute dose-ranging evaluation of the antidepressant properties of Sceletium tortuosum (Zembrin®) versus escitalopram in the Flinders Sensitive Line rat. J Ethnopharmacol. 2022 Feb 10;284:114550. do PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Sceletium and Phentermine Together: Common Questions

Is it safe to take Sceletium with Phentermine?
We do not list a known interaction between Sceletium and Phentermine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Sceletium and Phentermine have any of the same side effects?
Yes — our sources link each of them separately to 4 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Are Sceletium and Phentermine used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Sceletium in each. That is a conversation for your prescriber, especially if Phentermine is being adjusted to a target.
How was the Sceletium and Phentermine combination checked?
Interactions in our licensed database are recorded against drug classes. Phentermine is filed under 2 classifications, and Sceletium has documented interactions with 1 drug class — none of Phentermine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Sceletium interact with any other medications?
Yes. Sceletium has 248 documented drug interactions in our database — Phentermine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Phentermine interact with any supplements?
Yes. Phentermine has documented interactions with 61 supplements in our database — Sceletium is not one of them. The Phentermine interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Phentermine and Sceletium?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.