
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.
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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.
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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.
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 months ago
Been dealing with burnout for the better part of a year and my naturopath suggested this alongside some adaptogenic herbs. Three weeks in and my afternoon energy crashes have noticeably reduced. Not a dramatic overnight shift, but a steady, quiet improvement that I'm genuinely grateful for.
4 months ago
Was recommended this by my functional medicine practitioner after a rough patch of overtraining. About four weeks in, my morning cortisol felt more even and I stopped waking up at 3am anxious. Takes a bit of patience but worth sticking with.
5 months ago
I've tried a couple of cheaper brands and they just didn't deliver the same results. The manufacturing standard here is clearly a cut above. My integrative GP recommended this specifically and I can see why. Steady improvement in fatigue over about six weeks.
5 months ago
Does what it says. My 11am slump is basically gone now. Would buy again without question.
5 months ago
Took this on the advice of my nutritional therapist whilst working through a post-viral fatigue protocol. It's subtle — not a stimulant at all — but after about a month I noticed I was responding to stress more calmly rather than feeling completely wiped out by it. Impressed with the quality.
5 months ago
My practitioner had me on two capsules twice daily and a single bottle ran out in under three weeks. The product itself seems effective — my afternoon fatigue is better — but at that dose the cost adds up quickly. Would be good if a larger bottle size was available.
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