Ashwagandha for Stress and Cortisol: when to take it, how long, which dose
The package names one time of day. Your body runs on another. Why the timing of intake may fit your cortisol curve, and why a time-limited course makes more sense than a permanent companion.
The question "morning or evening?" sounds like a detail. But it is really the question behind the question: What exactly is this plant supposed to change in your rhythm? If you don't know that, you may take it at the wrong time, for the wrong reason or for too long.
You've made your decision. The jar is sitting in the kitchen. The label says: one capsule daily with a meal. And then you stand there in the morning and wonder whether breakfast is the right meal. Or maybe dinner, since what you actually want is better sleep.
You google it. One site says morning, for energy. Another says evening, for calm. A third says it doesn't matter. They all sound certain. None of them asks about you.
In this text, I'd like to offer you a different perspective. Not the only valid one, but a reasoned one. It goes like this: The timing of intake can be guided by your personal stress pattern, meaning by when your stress axis is too loud, too quiet or out of sync over the course of the day. And for that, it is worth getting to know this pattern once.
What you can expect here
- Why cortisol follows a daily curve rather than a fixed number
- What your chronotype has to do with your morning cortisol
- Which doses and extracts have been studied
- How timing can be derived from your stress pattern
- Why a course fits the data better than continuous use
- Liver, thyroid, pregnancy, interactions
- What the BfR and Denmark say about ashwagandha
- How a salivary daily profile works
Why the package insert is looking at the wrong clock
Imagine your stress axis like the tides of the sea. In the morning the tide comes in, at midday the water recedes, at night it is low tide. That is not a flaw. That is the plan. Cortisol is the water in this picture.
The control runs through the HPA axis: hypothalamus, pituitary gland, adrenal cortex. The hypothalamus is the weather station, the pituitary the switchboard, the adrenal gland the production site. At the end, cortisol reports back and slows the chain down again. A thermostat that usually works with remarkable precision.
The first hour after waking is especially striking. In the first 30 to 45 minutes, cortisol rises markedly. Experts call this the cortisol awakening response. It is something like the ignition spark for your day: blood sugar up, attention on, immune system in daytime readiness.
In 2017, a research group at Northwestern University reviewed the literature on the diurnal cortisol slope, 179 associations from 80 studies.
Overall, a flatter slope from morning to evening was associated with poorer physical and mental health, in 10 of 12 areas examined. The association was clearest for immune and inflammatory markers.
For you, this means: it is not only the amount that counts, but the shape of the curve. Whether a flat curve is a cause or a consequence of illness, the authors leave open.
Adam EK et al. Psychoneuroendocrinology. 2017;83:25-41. DOI: 10.1016/j.psyneuen.2017.05.018Lark or owl: your chronotype shifts the tide
Now it gets personal. The tides are not the same for everyone. Some people are larks, awake early and tired early. Others are owls who only really arrive in the evening.
In 2005, a research group at the University of Trier measured salivary cortisol in the first hour after waking in 112 young men and compared it with their chronotype.
Morning types showed higher cortisol levels in this first hour than evening types. The difference could not be explained by waking time or sleep duration. A follow-up study of 112 middle-aged teachers also found indications of higher daytime levels in morning types.
For you, this means: two people with the same stress can have completely different curves. A one-size-fits-all time of day ignores exactly these differences.
Kudielka BM et al. Biol Psychol. 2006;72(2):141-146. DOI: 10.1016/j.biopsycho.2005.08.003 · Kudielka BM et al. J Psychosom Res. 2007;62(5):595-596. DOI: 10.1016/j.jpsychores.2007.03.016Three stress patterns, schematic
Schematic illustration only, not measurements from any specific person and not reference ranges.
"I'm stressed" describes a feeling. It says nothing about when your stress axis is out of sync. Too loud in the evening, overshooting in the morning or flat all day are three different states.
A plant that was able to lower measured cortisol in studies does not fit these three states equally well. It may not fit one of them at all.
And now you know why the time printed on the package is more a habit of the manufacturer than an answer to your body.
What studies show about dose and duration
Maybe you've put three products side by side and noticed: each one lists a different number of milligrams. That is not arbitrary. It is because "ashwagandha" is not a uniform substance.
Studies work with different extracts. Sometimes from the root only, sometimes from root and leaf, sometimes aqueous, sometimes made with a different process. The milligram figure of one extract is therefore not simply comparable with that of another. Ground coffee and espresso concentrate don't have the same dose per gram either.
In 2012, a clinic in Hyderabad studied 64 adults with chronic stress. The active group received 300 milligrams of a high-concentration full-spectrum root extract twice daily for 60 days.
The researchers observed a clear improvement on all stress questionnaires and a significant reduction in serum cortisol compared with placebo. Side effects were mild and comparable in both groups.
For you, this means: this study still shapes many package labels today. It ran for two months, not two years.
Chandrasekhar K et al. Indian J Psychol Med. 2012;34(3):255-262. DOI: 10.4103/0253-7176.106022In 2019, a team from Thane compared 125 milligrams twice daily, 300 milligrams of root extract twice daily and placebo over eight weeks in 60 stressed adults.
Both doses lowered stress scores and serum cortisol. At 600 milligrams per day, the effect was statistically clearer than at 250 milligrams. Sleep quality also improved compared with placebo.
For you, this means: more may have achieved somewhat more in this study. It does not mean that more is automatically better, because the safety data only cover eight weeks.
Salve J et al. Cureus. 2019;11(12):e6466. DOI: 10.7759/cureus.6466In 2019, an Australian group at Murdoch University gave 60 stressed adults 240 milligrams of the standardized extract Shoden once daily for 60 days.
Anxiety scores fell, and morning cortisol dropped markedly. Less noticed: DHEA-S, another adrenal hormone, also fell significantly compared with placebo.
For you, this means: the plant appears not only to take away "too much cortisol", but to dampen the adrenal axis somewhat overall. With an already flat curve, that is not a desirable goal.
Lopresti AL et al. Medicine (Baltimore). 2019;98(37):e17186. DOI: 10.1097/MD.0000000000017186| Study | Extract, as named | Daily dose | Schedule | Duration |
|---|---|---|---|---|
| Hyderabad 2012 | High-concentration full-spectrum root extract | 600 mg | 2 x 300 mg | 60 days |
| Thane 2019 | Aqueous root extract | 250 or 600 mg | 2 x 125 or 2 x 300 mg | 8 weeks |
| Murdoch 2019 | Standardized extract Shoden | 240 mg | 1 x daily | 60 days |
| Kolkata 2024 | Aqueous root and leaf extract | 125, 250 or 500 mg | per day | 8 weeks |
| Lucknow 2020 (safety) | Root extract | 600 mg | 2 x 300 mg | 8 weeks |
Study doses from the literature. Not a dosing recommendation. Extracts are not interchangeable.
In 2024, a research unit in Kolkata compared three doses of an aqueous root and leaf extract, 125, 250 and 500 milligrams per day, over eight weeks in adults with high perceived stress.
All three doses reduced mild to moderate chronic stress, with a dose-dependent pattern. Of 131 people enrolled, 98 were analyzed.
For you, this means: for some extracts, even low amounts have been studied. The dose on your jar only tells you something if you know which extract is inside.
Pandit S et al. Nutrients. 2024;16(9):1293. DOI: 10.3390/nu16091293In 2022, a group at the University of Tehran pooled twelve randomized trials with 1,002 people. Stress and anxiety decreased compared with placebo, and the most favorable dose range for stress was 300 to 600 milligrams per day. The authors themselves rated the certainty of the evidence as low.
A 2025 meta-analysis separated lab value and experience: cortisol fell by 1.16 micrograms per deciliter, while perceived stress did not differ significantly from placebo.
For you, this means: the direction is recognizable, but the size of the effect varies widely. A lower lab value is not yet a better life.
Akhgarjand C et al. Phytother Res. 2022;36(11):4115-4124. DOI: 10.1002/ptr.7598 · Albalawi AA. Nutr Health. 2025;31(4):1395-1408. DOI: 10.1177/02601060251363647In 2021, a group at Universiti Sains Malaysia analyzed five randomized trials on sleep with 400 people.
The overall effect was small but significant. It was clearer in diagnosed insomnia, at 600 milligrams per day or more, and with at least eight weeks of use.
For you, this means: if your problem is switching off in the evening, the data are comparatively strongest. At the same time, the authors stress that safety data for long-term use are lacking.
Cheah KL et al. PLoS One. 2021;16(9):e0257843. DOI: 10.1371/journal.pone.0257843A study dose is not a dosing recommendation. It is the amount observed in a specific group, with a specific extract, over a specific period.
The more useful question is not "how much?", but "which extract, for which pattern, for how long, and how will I notice that it is enough?".
And now you know why two milligram figures on two jars don't have to have anything to do with each other.
When to take ashwagandha: timing based on your stress pattern
Do you know the feeling of being dead tired in the evening and still lying awake in bed? Or waking up in the morning with a pounding heart before the alarm goes off? Or walking through the whole day as if behind glass, never fully awake, never really tired?
These are three different stories. And here comes the perspective that I consider useful in functional medicine. I deliberately keep it separate from what studies have tested.
Supported by studies: Ashwagandha was given in fixed schedules, mostly twice daily, sometimes once daily. In several studies, it lowered measured cortisol.
Not studied: No trial I know of has compared morning with evening intake or aligned the timing with an individual cortisol profile. What follows is a physiologically reasoned clinical consideration, not a tested rule.
Pattern 1: too loud in the evening
The curve does not drop in the afternoon. You are tired but wired. Falling asleep takes a long time. Thoughts keep circling.
Here, a dose later in the day seems biologically reasonable, because the goal is winding down in the evening. The sleep data fit this picture best.
Timing rather latePattern 2: overshooting in the morning
The awakening response is very high, often in larks. You start the day tense, with restlessness or a knot in your stomach, and are already drained by midday.
Here, an earlier dose may be more plausible, so the plant can act in the phase when the axis is loudest.
Timing rather earlyPattern 3: flat
No clear morning rise, no clear decline. The day is a grey line. Often there is a different problem behind this, such as sleep quality, light, iron or the thyroid.
A remedy that can dampen the axis further may not be a good fit here. First the cause, then the plant.
Rather not a good fitThe label said morning, the body said evening
I know this pattern very well. Someone comes in saying that ashwagandha "didn't do anything" or "felt strange". When I ask when the capsule was taken, the answer is almost always: the way it said on the jar.
Behind this statement there is no mistake on the person's part. There is a question that nobody asked: at what time of day is your stress axis actually out of balance? Sometimes the answer is surprising, and sometimes the profile shows that ashwagandha is not the right building block at all.
The lesson in one sentence: a remedy can only fit as well as the question it is meant to answer.
Timing is not a matter of taste. It is a translation of your pattern into a time of day. Without a pattern, every time of day remains a guess.
And now you know why the question "morning or evening?" cannot have a good answer without looking at your curve.
How long? A course instead of a permanent companion
Maybe you've been taking ashwagandha for a year already. It feels harmless, just a plant. You've never thought about stopping, because after all it's "natural".
Here it is worth taking an honest look at the timeline of the research. Almost all controlled studies ran for eight weeks or 60 days. A safety study from Lucknow with 80 healthy people found no abnormalities in blood count, liver and thyroid values on 300 milligrams twice daily over eight weeks. The authors themselves write that long-term studies are lacking.
This study specifically asked about safety, not effect. Over eight weeks, liver values, blood count, vital signs and the thyroid profile remained unchanged compared with placebo.
That is reassuring news for the period studied and for healthy people. For a year, for people with pre-existing conditions or for combinations with medication, it says nothing.
Verma N et al. Complement Ther Med. 2021;57:102642. DOI: 10.1016/j.ctim.2020.102642Receptor habituation: a legitimate question without a ready answer
Your body is a learning system. When it receives a signal permanently, it often adjusts its receivers. You know this from coffee: the first cup after a break feels stronger than the tenth in everyday life.
Whether something like this happens with ashwagandha has not been studied in humans. However, a recent critical review explicitly discusses possible suppression of adrenal function as a risk with longer or high-dose use. Together with the drop in DHEA-S in the Australian study, that is reason enough for me not to dampen the axis from the outside permanently without checking what it is doing.
A course has a beginning, a goal and an end. Continuous use only has a beginning. The study data fit the course.
What this means as a direction, not as a prescription:
First know the pattern
A salivary daily profile can show whether your axis tends to be too loud in the evening, overshooting in the morning or flat. Without this information, the decision remains trial and error.
Name a goal
Falling asleep more easily, starting the day more calmly, less tension in the afternoon. A concrete goal makes it possible to check later whether something has changed.
Set a time limit
A period oriented to the duration of the studies, with a fixed date for reassessment, instead of open-ended intake without an end.
Measure again and decide anew
Has the profile changed? Has your experience changed? Both together form the basis for deciding whether a break, an end or a different path makes sense.
"Herbal" does not mean "harmless forever". It only means that the active substance comes from a plant. Digitalis comes from a plant, too.
And now you know why, with ashwagandha, I prefer to speak of a monitored course rather than a companion for life.
Safety: what you should know before the first capsule
This section is not here to scare you. It is here so that you can make an informed decision. With plants, risks are often passed over in silence, as if nature were automatically gentle.
Liver: rare, but documented
In 2020, a research group from Reykjavík, together with the US Drug-Induced Liver Injury Network, described five people with liver injury after ashwagandha. After 2 to 12 weeks, jaundice, nausea and itching occurred. In four of those affected, liver values recovered within 1 to 5 months.
In 2023, a series from Kerala followed with eight cases involving products that contained only ashwagandha. Five had pre-existing liver disease; three of them developed acute-on-chronic liver failure and died. Chemical analysis found no contaminants.
For you, this means: the risk is rare, measured against how widely it is used. With existing liver disease, however, it should be taken seriously. The US database LiverTox lists ashwagandha as a rare cause of clinically apparent liver injury with a cholestatic or mixed pattern.
Björnsson HK et al. Liver Int. 2020;40(4):825-829. DOI: 10.1111/liv.14393 · Philips CA et al. Hepatol Commun. 2023;7(10):e0270. DOI: 10.1097/HC9.0000000000000270Thyroid: T4 can rise
A clinic in Varanasi gave 50 people with subclinical hypothyroidism 600 milligrams of root extract daily or placebo for eight weeks.
On ashwagandha, T3 and T4 rose significantly and TSH fell. A case report from Japan also describes painless thyroiditis with hyperthyroidism after two months of use in a previously healthy man, which subsided after stopping.
For you, this means: what may look favorable in mild hypothyroidism can go in the wrong direction in hyperthyroidism, in Hashimoto's or while taking thyroid hormones.
Sharma AK et al. J Altern Complement Med. 2018;24(3):243-248. DOI: 10.1089/acm.2017.0183 · Hayashi M et al. Cureus. 2024;16(3):e55352. DOI: 10.7759/cureus.55352What authorities say
In September 2024, the German Federal Institute for Risk Assessment (BfR) issued a warning about food supplements containing ashwagandha. It advises children, pregnant and breastfeeding women and people with liver disease against using them. For everyone else, it recommends caution, because side effects have rarely been recorded systematically in the studies. Among other things, it mentions gastrointestinal complaints, dizziness, drowsiness and possible effects on the immune system, cortisol, blood sugar, thyroid and sex hormones.
Denmark banned ashwagandha in foods and food supplements in 2023 after an assessment by the Technical University of Denmark could not establish a safe intake level. A 2025 review describes that a review procedure has been recommended at EU level that could lead to a restriction.
Fairness is part of this: experts from industry and research criticize that the Danish assessment did not cleanly separate root and leaf. I think both sides deserve to be taken seriously. For you, this mainly means: there is open uncertainty here, not established safety.
- Pregnancy and breastfeeding: do not use. Robust human data are lacking, and the BfR explicitly advises against it.
- Liver disease or abnormal liver values: do not use; the severe cases occurred in people with pre-existing disease.
- Thyroid disease, Hashimoto's, thyroid hormones: only with monitoring of the values.
- Autoimmune diseases: ashwagandha is described as immunomodulating. How this plays out in an overactive immune system has not been studied sufficiently.
- Immunosuppressants: possible counteraction against an intended dampening of the immune system; combine only in coordination with a physician.
- Sedatives and sleeping pills, alcohol: dampening effects can add up.
- Glucose-lowering and blood pressure medication: caution because of possible effects on blood sugar and circulation; the human data are thin here.
- Warning signs during use: jaundice, dark urine, pale stools, persistent itching, racing heart, unintended weight loss. In that case, stop and seek medical evaluation.
A 2026 critical review summarizes preclinical and clinical data. It mentions gastrointestinal complaints, hypersensitivity reactions, liver injury and effects on the endocrine system, including hyperthyroidism and possible adrenal suppression. Reactive intermediates might form via cytochrome P450 enzymes.
A second review of herbal remedies for anxiety and sleep disorders warns of drug interactions via these liver enzymes and of excessive sedation in combination with other dampening substances.
For you, this means: if you take medication regularly, ashwagandha belongs on the list you discuss with a physician.
Kumar A et al. Phytother Res. 2026;40(8):4913-4931. DOI: 10.1002/ptr.70158 · Căuș MN et al. Pharmaceuticals (Basel). 2026;19(3):399. DOI: 10.3390/ph19030399A plant that can measurably act on cortisol, the thyroid and the immune system is not a lifestyle drink. Exactly what makes it interesting also calls for caution.
And now you know why the safety question comes before the timing question.
The salivary daily profile: the basis for any timing
Maybe your cortisol has been measured in blood before, at some point in the morning. Result: within the normal range. And yet you don't feel normal.
That is not a contradiction. A single value is a snapshot. The daily curve is a film. For the timing question, you need the film.
In 2016, an expert panel of the International Society of Psychoneuroendocrinology led from TU Dresden published guidelines for measuring the cortisol awakening response.
Their central message: the measurement stands or falls with the exact timing. The first sample belongs at the moment of waking, the others at fixed intervals afterwards. Even small delays can distort the result. Factors such as waking time, sleep and medication should also be recorded.
For you, this means: a salivary profile is only as good as your care in collecting it. In return, it is more informative than a single blood value.
Stalder T et al. Psychoneuroendocrinology. 2016;63:414-432. DOI: 10.1016/j.psyneuen.2015.10.010Typical sampling times
- Right on waking, still in bed
- 30 minutes after waking
- 45 minutes after waking
- In the afternoon
- Before going to bed
What you note down
- Exact waking time and time of each sample
- Whether you are a lark, an owl or in between
- Sleep quality the night before
- Medication, especially cortisone or hormones
- A normal day, not an exceptional one
And now you know why the start of an ashwagandha course is not the jar, but a small tube of saliva.
Three levers you can use right away
Energy is not a luxury. A rhythm that carries you in the morning and lets you go in the evening is a form of freedom. You can start these three steps today, without any capsule.
Your next steps
- Observe your day for one week. When are you wired, when drained, when can't you settle down? Make a short note. That is your first clue to your pattern.
- Check your reasons for exclusion. Pregnancy, breastfeeding, liver, thyroid, autoimmune disease, regular medication. If one of these applies, that calls for a conversation, not a self-experiment.
- If you use ashwagandha, give it a framework. A goal, a time period, a date for reassessment, ideally with a profile before and after.
Frequently asked questions about intake, duration and dose
When to take ashwagandha: morning or evening?
The research does not provide a universal answer. Most stress studies split the extract into two doses a day, and one Australian study gave it once daily. No trial has compared morning with evening intake so far. From a physiological point of view, it is plausible to link the timing to your own cortisol pattern: if you cannot wind down in the evening and struggle to fall asleep, a dose later in the day seems reasonable. If you already start the day wired, an earlier dose may make more sense. If your curve is flat, ashwagandha may not be the right tool at all. This is a clinical consideration, not a rule tested in studies.
Which doses of ashwagandha have been studied?
These are study doses, not a recommendation for you. A 2012 study from Hyderabad used 300 milligrams of a high-concentration full-spectrum root extract twice daily for 60 days. A 2019 study from Thane compared 125 and 300 milligrams of root extract, each twice daily, over eight weeks. A 2019 Australian study gave 240 milligrams of the standardized extract Shoden once daily for 60 days. A 2024 study from Kolkata tested 125, 250 and 500 milligrams per day of an aqueous root and leaf extract. A dose-response analysis found the most favorable range for stress at 300 to 600 milligrams per day. Because the extracts differ, these numbers cannot simply be transferred to any product.
How long should you take ashwagandha?
The controlled studies usually ran for eight weeks or 60 days. For this period, there are data on effects and tolerability. For use over many months or years, robust controlled data are lacking. That is why, in my view, a lot speaks for a time-limited course with a clear goal, a measurement beforehand and a reassessment afterwards. Taking it indefinitely without monitoring goes beyond what has been studied.
Does ashwagandha lower cortisol?
In several studies, measured cortisol decreased. A 2025 meta-analysis of seven randomized trials found a reduction of 1.16 micrograms per deciliter. The same analysis, however, found no significant effect on perceived stress. In an Australian study, DHEA-S fell alongside morning cortisol. For you, this means: ashwagandha appears to dampen the stress axis somewhat overall. Whether that is desirable in your case depends on your starting pattern.
Can the body get used to ashwagandha?
Whether habituation or a waning effect occurs in humans has not been systematically studied so far. From the physiology of the stress axis, we know that feedback loops can adapt to persistent signals. A recent review also discusses possible suppression of adrenal function as a risk with longer use. This is not proof, but it is a good reason not to take it indefinitely and to monitor the course.
Can ashwagandha affect the thyroid?
Yes, that is possible. In a small randomized trial of 50 people with subclinical hypothyroidism, T3 and T4 rose significantly and TSH fell on 600 milligrams of root extract daily over eight weeks. There is also a case report of painless thyroiditis with hyperthyroidism after two months of use, which subsided after stopping. In healthy people, the thyroid profile remained unchanged in an eight-week safety study. If you have a thyroid condition or take thyroid hormones, you should only use ashwagandha under medical supervision.
Can ashwagandha harm the liver?
There are documented cases, even though they are rare. A case series from Iceland and the US Drug-Induced Liver Injury Network described five people with jaundice and itching after 2 to 12 weeks of use. Liver values recovered in four of them within 1 to 5 months. A series from India described eight cases with single-ingredient products; three people with pre-existing liver disease died. The US database LiverTox lists ashwagandha as a rare cause of clinically apparent liver injury. Jaundice, dark urine, pale stools or persistent itching during use are a reason to stop immediately and seek medical evaluation.
What do the BfR and Denmark say about ashwagandha?
In September 2024, the German Federal Institute for Risk Assessment (BfR) issued a warning about food supplements containing ashwagandha. It advises children, pregnant and breastfeeding women and people with liver disease against taking it, and recommends caution for everyone else, because possible side effects have rarely been recorded systematically in the studies. Denmark banned ashwagandha in foods and food supplements in 2023 after an assessment by the Technical University of Denmark could not establish a safe intake level. At EU level, a review procedure has been recommended that could lead to a restriction. These assessments are not undisputed, but they belong to a fair overall picture.
Which medications can ashwagandha interact with?
Reviews mainly mention sedatives and sleeping pills such as benzodiazepines, because dampening effects can add up, as well as interactions via cytochrome P450 enzymes in the liver. Because of possible effects on the thyroid and immune system, caution is advised with thyroid hormones and immunosuppressants. The BfR also points to possible effects on blood sugar, which may be relevant with glucose-lowering drugs. Reviews also advise caution with blood pressure medication, although the human data on this are thin. If you take medication regularly, you should discuss ashwagandha with a physician beforehand.
How do you measure the diurnal cortisol curve?
The most informative option is a salivary daily profile with several samples that you collect at home. Typical samples are taken right after waking, 30 and 45 minutes later, in the afternoon and before going to bed. International consensus guidelines emphasize that the first sample really has to be taken at the moment of waking, because even small delays can distort the result. A single blood value in the morning says little about the rhythm.
Further reading in the ViveCura guide
Timing is one question. These topics are physiologically closely connected to it.
Medicinal plants
Phytotherapy with evidence and limits
You are hereAshwagandha
Effects and who it may make sense for
Hormones
Cortisol, thyroid, sex hormones
Burnout
When exhaustion won't go away
Sleep
Rhythm, deep sleep, regeneration
Iron
A frequently overlooked cause of fatigue
Vitamin D
Taking it correctly, with magnesium and K2
Supplements
What makes sense and what doesn't
Sources
- Chandrasekhar K, Kapoor J, Anishetty S. A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian J Psychol Med. 2012;34(3):255-262. DOI: 10.4103/0253-7176.106022 [RCT, n=64]
- Salve J, Pate S, Debnath K, Langade D. Adaptogenic and anxiolytic effects of ashwagandha root extract in healthy adults: A double-blind, randomized, placebo-controlled clinical study. Cureus. 2019;11(12):e6466. DOI: 10.7759/cureus.6466 [RCT, n=60]
- Lopresti AL, Smith SJ, Malvi H, Kodgule R. An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled study. Medicine (Baltimore). 2019;98(37):e17186. DOI: 10.1097/MD.0000000000017186 [RCT, n=60]
- Pandit S, Srivastav AK, Sur TK et al. Effects of Withania somnifera extract in chronically stressed adults: A randomized controlled trial. Nutrients. 2024;16(9):1293. DOI: 10.3390/nu16091293 [RCT, n=98 analyzed]
- Akhgarjand C, Asoudeh F, Bagheri A et al. Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trials. Phytother Res. 2022;36(11):4115-4124. DOI: 10.1002/ptr.7598 [Meta-analysis, k=12, n=1,002]
- Albalawi AA. Dual impact of Ashwagandha: Significant cortisol reduction but no effects on perceived stress. A systematic review and meta-analysis. Nutr Health. 2025;31(4):1395-1408. DOI: 10.1177/02601060251363647 [Meta-analysis, k=7, n=488]
- Cheah KL, Norhayati MN, Husniati Yaacob L, Abdul Rahman R. Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis. PLoS One. 2021;16(9):e0257843. DOI: 10.1371/journal.pone.0257843 [Meta-analysis, k=5, n=400]
- Verma N, Gupta SK, Tiwari S, Mishra AK. Safety of ashwagandha root extract: A randomized, placebo-controlled study in healthy volunteers. Complement Ther Med. 2021;57:102642. DOI: 10.1016/j.ctim.2020.102642 [RCT, n=80]
- Sharma AK, Basu I, Singh S. Efficacy and safety of ashwagandha root extract in subclinical hypothyroid patients: A double-blind, randomized placebo-controlled trial. J Altern Complement Med. 2018;24(3):243-248. DOI: 10.1089/acm.2017.0183 [RCT, n=50]
- Hayashi M, Hamada H, Azuma SI, Hayashi K. Painless thyroiditis by Withania somnifera (Ashwagandha). Cureus. 2024;16(3):e55352. DOI: 10.7759/cureus.55352 [Case Report]
- Björnsson HK, Björnsson ES, Avula B et al. Ashwagandha-induced liver injury: A case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int. 2020;40(4):825-829. DOI: 10.1111/liv.14393 [Case Series, n=5]
- Philips CA, Valsan A, Theruvath AH et al. Ashwagandha-induced liver injury: A case series from India and literature review. Hepatol Commun. 2023;7(10):e0270. DOI: 10.1097/HC9.0000000000000270 [Case Series, n=8]
- Kumar A, Sah BK, Ahmad F, Jamwal V, Sahu SK. Potential adverse effects of Ashwagandha: A critical review of preclinical and clinical evidence. Phytother Res. 2026;40(8):4913-4931. DOI: 10.1002/ptr.70158 [Review]
- Căuș MN, Lupoae M, Chițescu CL. Efficacy and safety of herbal supplements with anxiolytic, antidepressant, and sedative action: A review of clinical data and toxicological risks. Pharmaceuticals (Basel). 2026;19(3):399. DOI: 10.3390/ph19030399 [Review]
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