Stress

Eleuthero’s adaptogenic effect is real but modest and preparation-dependent, mechanistically tied to HPA-axis regulation and heat-shock-protein (Hsp70) signalling ^{1Reference 1Panossian A · 2009ReviewEvidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity — reviewView study →}; a review rated the human evidence for mild fatigue and weakness as “good” and the EMA accepts the root as a traditional herbal medicine for asthenia ^{1,2,3Reference 1Panossian A · 2009ReviewEvidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity — reviewView study →Reference 2Patyra A et al. · 2025ReviewEleutherococcus root: a comprehensive review of its phytochemistry and pharmacological potential in the context of its adaptogenic effect — reviewView study →Reference 3European Medicines Agency · 2006ReviewEuropean Medicines Agency, Committee on Herbal Medicinal Products (HMPC). (2006/2014). Community herbal monograph on Eleutherococcus senticosus (Rupr. et Maxim.) Maxim., radix — Doc. EMEA/HMPC/244569/2006 (traditional use for asthenia). https://www.ema.europa.eu/en/medicines/herbal/eleutherococci-radixView study →}.

Adding 120 mg/day to stress-management training gave negligible extra benefit ^{4Reference 4Schaffler K et al. · 2013RCTNo benefit adding Eleutherococcus senticosus to stress management training in stress-related fatigue — randomised controlled studyView study →}, effects are clearest only in already-fatigued or elderly people, and no trial shows a durable benefit in healthy adults.

Tulsi’s best human evidence: a six-week randomised, double-blind, placebo-controlled trial of the standardised extract OciBest (1200 mg actives/day, n=150) significantly reduced self-rated stress symptoms — forgetfulness, exhaustion, sleep and sexual problems — versus placebo ^{5Reference 5Saxena et al. · 2012RCTEfficacy of an extract of Ocimum tenuiflorum (OciBest) in the management of general stress — randomised placebo-controlled trialView study →}, with a 2022 8-week RCT of a standardised Ocimum extract (125 mg/day, n=100) also improving stress and sleep measures ^{6Reference 6Lopresti et al. · 2022RCTA randomised, double-blind, placebo-controlled trial investigating the effects of a standardised Ocimum tenuiflorum extract — randomised controlled trialView study →}. Here classical rasayana use and modern trials converge.

The trials are small, use different preparations and doses, and rest on subjective symptom scales rather than physiological stress markers.

In an fMRI study, a single 25 mg dose of Zembrin, a proprietary kanna extract, dampened amygdala threat-reactivity and reduced its coupling to the hypothalamus, pointing to a down-regulated acute stress response ^{7Reference 7Terburg et al. · 2013Acute effects of Sceletium tortuosum (Zembrin), a dual 5-HT reuptake and PDE4 inhibitor, in the human amygdala and its connection to the hypothalamus}. The study measured a neuroimaging surrogate after one dose, with no perceived-stress or cortisol endpoint.

Shatavari is a classical adaptogen/nervine tonic, but the only human stress signal is secondary: the 12-week PCOS RCT recorded a large, significant fall in Perceived-Stress-Scale scores (PSS −6.64; p<0.0001) independent of any hormonal change ^{11Reference 11Mhatre Y et al. · 2026RCTEfficacy and safety of Shatavari root extract in women with polycystic ovarian syndrome — randomised, double-blind, placebo-controlled trialView study →}. Beyond that, the anti-stress use rests on reviews and preclinical monoaminergic/GABAergic mechanism ^{12,13Reference 12Singh N et al. · 2023ReviewAdaptogenic property of Asparagus racemosus — reviewView study →Reference 13Majumdar S et al. · 2021ReviewNeuro-nutraceutical potential of Asparagus racemosus — reviewView study →} — no dedicated human anxiety/stress RCT exists.

Transdermal ylang-ylang oil raised self-rated calmness alongside a fall in blood pressure and pulse ^{14Reference 14Hongratanaworakit et al. · 2006Clinical trialRelaxing effect of ylang ylang oil on humans after transdermal absorption — clinical trialView study →}, and the blended Korean aromatherapy nursing trials reported reduced serum cortisol, catecholamines and improved heart-rate-variability (autonomic) measures in stressed/hypertensive populations ^{15,16,17Reference 15Hwang · 2006RCTEffects of the inhalation method using essential oils on blood pressure and stress responses in essential hypertension — randomized controlled trial (oil blend)View study →Reference 16Cha et al. · 2010Clinical trialEffects of aromatherapy on autonomic nervous system, aortic pulse wave velocity and augmentation index in essential hypertension — controlled clinical trial (oil blend)View study →Reference 17Song et al. · 2018RCTEffects of aromatherapy on stress responses, autonomic activity and blood pressure in patients undergoing coronary angiography — non-randomized controlled trial (oil blend)View study →}.

The signal is a general “harmonising” autonomic calming rather than a dedicated stress endpoint, and the cortisol/catecholamine data come from oil blends, not ylang-ylang alone.

POEE produced broad anti-stress effects in mice — better hypoxia endurance, prevention of stress-induced hyperglycaemia, HPA-axis dampening — which the authors read as adaptogen-like ^{8,9Reference 8Piato et al. · 2008Effects of Marapuama in the chronic mild stress model: further indication of antidepressant properties — animal studyView study →Reference 9Piato et al. · 2010AnimalAnti-stress effects of the “tonic” Ptychopetalum olacoides (Marapuama) in mice — animal studyView study →}. Rodent-only; the biphasic anxiety signal (anxiogenic at 30–300 mg/kg in one paradigm ^{10Reference 10da Silva et al. · 2002Anxiogenic properties of Ptychopetalum olacoides Benth. (Marapuama) — animal studyView study →}, anti-stress in others) is unresolved, and there is no human stress endpoint.

A traditional Western relaxing nervine, taken as a tea or tincture to ease stress and nervous tension. Its sedative research is animal work on anxiety and sleep; no study has measured a stress endpoint.

Cordyceps is taken as an adaptogenic tonic for stress resilience in traditional and Western herbalism. No study has measured its effect on the HPA axis or cortisol.

Best known for sleep, valerian also carries a preclinical anti-stress signal — valerenic acid lowered stress corticosterone and calmed limbic monoamine turnover in mice. There is no human trial with a stress endpoint.