Founding batch open — nothing charged until your order ships
Hericea
HericeaResearchIngredientsSceletium tortuosum (Zembrin®)

Ingredient Evidence Review

Sceletium tortuosum (Zembrin®)

Sceletium tortuosum (kanna)

Last updated 2026-05-19 · 3 primary citations

Mechanism

Zembrin® is a standardized extract of the South African plant kanna. It takes the edge off acute stress quickly — brain-imaging studies show it quiets the threat-detection circuitry — but without sedating you. The point is calmer, not slower.

Why we use it

High-stakes focus often requires acute anxiety modulation. Zembrin is the only botanical with replicated fMRI amygdala-decoupling signal at supplement doses.

How we dose it

Hericea uses 25 mg per serving (per AM stick pack). The clinical trial range that anchors this dose is 25–50 mg/day.

At the Zembrin® clinical RCT dose. Mesembrine-alkaloid-standardized branded form.

Quality & sourcing

Zembrin® HG&H Pharmaceuticals branded; mesembrine-alkaloid standardized.

HG&H Pharmaceuticals-licensed.

Cautions

  • consult physicianConsult physician if on SSRI/SNRI/MAOI antidepressants.

Primary literature

Terburg et al. (Northumbria) (2013)

Neuropsychopharmacology

fMRI RCT

Zembrin decoupled amygdala-hypothalamus reactivity to fearful faces.

Reay et al. (2020)

RCT

RCT · 1 weeks

Acute Zembrin improved cognitive performance under stress.

Systematic review (2024)

Meta-analysis

Meta-analysis

SMD 0.35 across Sceletium cognitive-mood endpoints.