
KSM-66 Ashwagandha
The most clinically studied ashwagandha extract, at the full 600mg dose the trials actually use.

£20.00
Glandular support for the system that carries you through demanding, depleting stretches, made to clinical standard.
ThorneAdrenal CortexWhat are you hoping to improve?
Pick a goal and we’ll tell you, honestly, whether Adrenal Cortex is the right fit, or what would suit you better.
When stress runs high for long enough, daily energy and resilience start to fray at the edges. The wired-but-tired feeling, the flat afternoons, the sense of running slightly behind your own day. Adrenal Cortex is a long-standing clinical tool for exactly those stretches. It is a glandular supplement derived from bovine adrenal cortex tissue, used by practitioners to support the body's own stress-response machinery and help steady cortisol's daily rhythm. It aims to restore capacity rather than borrow against it with a stimulant.

The most clinically studied ashwagandha extract, at the full 600mg dose the trials actually use.

An adaptogen for mental stamina, the one to reach for when fatigue, not anxiety, is the problem.

Calm, focused attention, and the amino acid that takes the jitter out of caffeine.
Interested in more
personalised recommendations?
Set up your WA\ Profile to connect your wearables, biomarkers and test results. Create a bespoke plan based on your unique biology. Expert-led, evidence-based.
Set up Profile nowWhen stress runs high for long enough, daily energy and resilience start to fray at the edges. The wired-but-tired feeling, the flat afternoons, the sense of running slightly behind your own day. Adrenal Cortex is a long-standing clinical tool for exactly those stretches.
It is a glandular supplement derived from bovine adrenal cortex tissue, used by practitioners to support the body's own stress-response machinery and help steady cortisol's daily rhythm. It aims to restore capacity rather than borrow against it with a stimulant.
Thorne make it to the standard that has earned the brand its place in clinical practice: clean, traceably sourced from grass-fed Argentinian cattle and precisely dosed, without the fillers that crowd lesser formulations.
Best used through genuinely demanding periods, and a natural companion to adaptogens like ashwagandha and rhodiola when the goal is steady, sustainable resilience.
When stress runs high for long enough, daily energy and resilience start to fray at the edges. The wired-but-tired feeling, the flat afternoons, the sense of running slightly behind your own day. Adrenal Cortex is a long-standing clinical tool for exactly those stretches.
We don't stock glandulars lightly. This is a single, traceable extract from grass-fed Argentinian cattle, made to Thorne's practitioner-grade standard, with no caffeine or synthetic hormones to mask what's actually going on.
Supports the body's own stress-response machinery and a healthier daily cortisol rhythm, aiming to restore capacity rather than borrow against it.
One capsule in the morning with food.
Take earlier in the day to support natural energy rhythm.
Use through demanding periods rather than indefinitely.
If you feel wired or restless, take less, or take a break.
The aim is steadiness, not stimulation.
A physician-led talk on the biology of chronic stress, and practical, evidence-based ways to steady a frayed system.
See our next stress talk
Overall sentiment
4 days ago
Gentle on a sensitive stomach, and I feel like myself again. I had tried two other glandulars before this and neither sat right.
1 week ago
I was sceptical about glandulars, but my mid-afternoon crash has genuinely eased. One capsule with breakfast and I forget about it.
2 weeks ago
Not a stimulant, which is exactly what I wanted. It took about ten days, then I realised I wasn’t dreading the afternoon any more.
3 weeks ago
Bought after a blood panel flagged a flat cortisol curve. Easy to take, no jitters, and the sourcing is refreshingly transparent.
1 month ago
Training hard through a stressful stretch and this has helped me bounce back between sessions. Already on my second bottle.
1 month ago
No frills, one ingredient, a sensible dose. I appreciate that it is designed to be used for a season rather than forever.
A blood test is the only way to know what your body actually needs. We’ll tell you which of these supplements is right for you.
Find your panel
A curated selection of products, tools and rituals, carefully chosen by our expert doctors, to benefit you on your wellness journey.
Loading the catalogue…