Ashwagandha for Anxiety: What the Research Shows, Dose and Safety (UK)

Does ashwagandha help with anxiety? What the trials show

Ashwagandha (Withania somnifera) is an Ayurvedic root sold in the UK as a food supplement. It has more anxiety trials than most herbs, which is why our guide to the best natural supplements for anxiety ranks it second on evidence. Here is what the main studies found:

The honest caveats:

• The individual trials above had 40 to 64 people each and lasted 6 weeks to about 2 months. Most were run in India, and two used an extract supplied by its maker.
• Most of these trials enrolled stressed but otherwise healthy adults, not people with a diagnosed anxiety disorder. The one trial in generalised anxiety disorder was tiny and added ashwagandha to prescribed medicine.
• Results varied a lot between trials, and the 2022 review rated the certainty of the evidence as low.
• Ashwagandha has no authorised health claims in the UK, so no product can promise it reduces anxiety.

What about people with a diagnosed anxiety disorder? Two newer reviews looked at this more closely:

• A 2025 review in the journal BJPsych Open pooled 14 trials with 713 people who had a diagnosed mental health condition, mostly anxiety disorders. The median dose was 600mg a day, usually for about 8 weeks. Anxiety scores fell more than with the comparison treatments, and side effects were no different. The authors flagged the small number of studies, wide differences between them and some outlier results, and called for larger trials.
• A 2024 review of 5 trials (254 people with anxiety or insomnia) found Hamilton anxiety scores about 6 points lower than placebo, but the trials disagreed with each other so much that the authors said bigger studies are needed to confirm it.

Promising for everyday stress, then, but not proven and no replacement for therapy or medicine. For its other uses, see what ashwagandha does.

What we still don’t know about ashwagandha and anxiety

• Whether it helps diagnosed anxiety disorders. Only a handful of small trials enrolled people with a diagnosis, and several added ashwagandha to prescribed medicine.
• How it compares with proven treatments. We found no large trials comparing it directly with CBT or prescribed anxiety medicines.
• Long-term safety. Trials ran for weeks, not years. The US National Center for Complementary and Integrative Health says it may be safe for up to three months.
• Rare harms. Trials of 40 to 64 people are far too small to pick up rare liver or thyroid reactions, which have come to light through case reports.
• Which extract and dose is best. Different branded extracts haven’t been tested against each other.
• Whether results hold up independently. Most trials ran in India, and several were funded or supplied by the extract’s maker.

Does ashwagandha help with OCD, ADHD or social anxiety?

• OCD: one 2016 trial gave 30 people with OCD, all already on SSRI antidepressants, 120mg of root extract a day or placebo for 6 weeks. Symptom scores fell more in the ashwagandha group, but one trial this small proves little.
• ADHD: we found no trials of ashwagandha on its own for ADHD. The one children’s trial we found used a multi-herb blend, and ashwagandha isn’t suitable for under 18s.
• Social anxiety, health anxiety and overthinking: we found no trials looking at these specifically. See social anxiety, health anxiety and how to stop overthinking.

iIf you have a diagnosis and take medicine, speak to your GP or psychiatrist before adding any supplement, and never stop prescribed medicine to try one.

Ashwagandha for stress: what the trials measured

Most ashwagandha “anxiety” trials are really stress trials. They recruited adults who said they felt under strain, then measured a stress questionnaire (the Perceived Stress Scale), an anxiety scale and often a cortisol test. So the stress evidence and the anxiety evidence largely come from the same small studies.

• Stress scores: in the 2012 trial of 64 adults with chronic stress, Perceived Stress Scale scores fell by 44% after 60 days on ashwagandha, against 5.5% on placebo. The 2024 review of 9 trials found perceived stress about 4.7 points lower than placebo.
• Cortisol: a 2025 review of 7 cortisol trials found cortisol about 1.2 micrograms per decilitre lower than with placebo.
• But not always both: the same 2025 review, 488 people in all, also pooled 6 trials of perceived stress and found no clear difference from placebo. Its author called it a “disconnect” between the hormone result and how people said they felt.

If stress is turning into constant worry, poor sleep or physical symptoms, read our guides to stress symptoms, how to relieve stress and high cortisol symptoms in women. The basics (sleep, movement, less caffeine and alcohol, someone to talk to) are worth sorting before any supplement.

How might ashwagandha work for anxiety?

Nobody knows for sure. The leading idea is that ashwagandha may act on the hypothalamic-pituitary-adrenal (HPA) axis, the system that releases the stress hormone cortisol. That theory comes from study findings rather than proof:

• Several trials measured lower cortisol in the ashwagandha group than on placebo, and the 2024 review found the same when it pooled them.
• The Lopresti trial also found falls in DHEA-S, another adrenal hormone, and its authors suggested any stress-relieving effect may run through the HPA axis.

Lower cortisol on a blood test isn’t the same as feeling calmer.

How much ashwagandha did anxiety trials use, and for how long?

These are the amounts studied, not a recommended dose:

• Range: 240mg to 1,000mg of root extract a day.
• Most common: 300mg twice a day (600mg a day). The 2022 review found the clearest stress results at 300 to 600mg a day.
• Extracts: the Chandrasekhar and Salve trials used KSM-66, a branded root extract, and the Lopresti trial used Shoden, another branded extract. Results from one extract may not apply to another, and plain root powder is much weaker.
• Length: 6 weeks to about 2 months in the trials above. No anxiety trial tells us about long-term use, and the US National Center for Complementary and Integrative Health says it may be safe for up to three months.

How long does it take? It isn’t a quick fix: trials measured results after weeks of daily use. Follow your product’s label, don’t stack several ashwagandha products, and keep a simple diary to judge it honestly. For timing, see when to take ashwagandha, and if worry keeps you awake, ashwagandha for sleep covers the sleep trials.

Which ashwagandha should I buy for anxiety?

Whether the label says ashwagandha, ashwaganda or Withania somnifera, it’s the same plant. What differs is which part of the plant is used, how it’s extracted and how much you get. No single type is proven best for anxiety, but these are the main options you’ll see in the UK:

What to look for on the label:

• Root, not leaf. Root and leaf have a different chemical make-up: leaf is richer in withaferin A, and a 2026 review found human data on leaf extracts sparse. It concluded there is more confidence in authenticated, standardised root preparations.
• A stated extract and amount. “Standardised to X% withanolides” plus the mg per capsule lets you compare it with the trials. A label that only says “ashwagandha 500mg” doesn’t tell you if that is extract or powder.
• Independent testing. Quality is patchy. In a US lab analysis of 25 ashwagandha supplements, only 10 met both British and US Pharmacopoeia standards, and only 2 were confirmed as root-only; the rest contained varying, sometimes undisclosed, amounts of leaf or stem.
• One product at a time. Don’t stack an ashwagandha capsule with a blend that also contains it, and don’t go above the label dose.

The branded extracts have the most trials partly because their makers fund or supply them (the 2012 KSM-66 and the Shoden trials both were). For questions specific to women or men, see ashwagandha for women and ashwagandha for men.

Can ashwagandha make anxiety worse?

In trials, side effects were mostly mild, such as drowsiness or an upset stomach. But a few people describe feeling restless, more anxious, or flat and emotionally numb, mostly in online forums rather than trials. If your anxiety or mood gets worse after starting it, stop, and speak to your GP if it doesn’t settle. Our ashwagandha side effects guide covers this in more detail.

One less obvious route is the thyroid. Rare case reports link ashwagandha to an overactive thyroid, and the NHS lists nervousness, anxiety, irritability and a fast heartbeat among its symptoms. If you feel jittery, shaky or your heart races after starting ashwagandha, stop and ask your GP about a thyroid blood test. More on this in who should avoid it.

Ashwagandha and panic attacks

Ashwagandha isn’t for panic attacks. We found no trials in panic disorder, and something studied over weeks of daily use can’t help in the moment.

The NHS page on panic disorder describes panic attacks as frightening but not dangerous, usually lasting 5 to 20 minutes. During one, it suggests staying where you are, breathing slowly and deeply, and reminding yourself it will pass. CBT is a main treatment, and you can self-refer in England. Our guide on how to stop a panic attack walks through what to do step by step.

If racing thoughts are more your pattern than sudden panic, see how to stop overthinking.

Ashwagandha vs other options for anxiety

Supplements are, at most, an add-on to the NHS first steps:

If ashwagandha isn’t suitable for you, magnesium is a gentler place to start: see magnesium for anxiety and ashwagandha vs magnesium. Or compare ashwagandha vs rhodiola and holy basil (tulsi). For everyday habits, read how to deal with anxiety.

Ashwagandha in Evopure products

Our Flow CBD Oil combines broad spectrum CBD (0% THC) with ashwagandha root and maca in MCT oil, as a daytime blend. It comes in 500mg and 1,000mg strengths in a 10ml bottle, and you can read more about the other herb in our guide to maca root. CBD isn’t a treatment for anxiety, and we don’t claim Flow treats or prevents anything. The same cautions apply as for any ashwagandha product, so read the safety section below and our guide to CBD and ashwagandha first.

The FSA’s 10mg a day figure is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication.

If you’d rather avoid ashwagandha, our Magnesium Glycinate Sleep Complex contains none. It combines magnesium bisglycinate and citrate with glycine, L-theanine, chamomile, passionflower, hops and oat straw. Magnesium contributes to normal psychological function and to the normal functioning of the nervous system.

Our Reishi Mushroom Adaptogenic Complex is a hot chocolate powder made with cocoa, reishi mushroom, maca, cinnamon and coconut sugar, with no ashwagandha. The cacao contains a little natural caffeine, so if caffeine leaves you jittery, have it earlier in the day (see does caffeine cause anxiety?). For how the two herbs differ, read reishi vs ashwagandha. All our products are for adults only.

Who should avoid ashwagandha

iThe FSA has said it would advise pregnant women and people with liver conditions to avoid ashwagandha supplements while its review continues (see what regulators say). Don’t take it, or check with your GP or pharmacist first, if any of these apply:

• Pregnant, could be pregnant, or breastfeeding. Avoid it. We don’t recommend our products during pregnancy or breastfeeding. Our guide to ashwagandha and breastfeeding explains why.
• Liver conditions. Avoid it. Liver injury is rare but has been reported. A 2026 review of published case reports found 25 people across 13 papers. It usually appeared after weeks of use, often with jaundice and itching, and most people recovered after stopping. One person needed a liver transplant, and three people who already had cirrhosis died. Stop and see your GP if you notice yellow skin or eyes, dark urine or itching.
• Thyroid conditions or thyroid medicine. Ashwagandha may raise thyroid hormone levels and interact with thyroid medicines. In a small 2018 trial, 600mg a day for 8 weeks shifted thyroid hormone results in people with a mildly underactive thyroid, and case reports describe an overactive thyroid that settled once ashwagandha was stopped. An overactive thyroid can itself cause nervousness, anxiety, palpitations and poor sleep, so new symptoms like these are worth a GP visit and a blood test. See overactive thyroid symptoms and underactive thyroid symptoms.
• Autoimmune conditions such as lupus, multiple sclerosis or rheumatoid arthritis, unless your doctor agrees.
• Antidepressants, anti-anxiety medicines, sleeping tablets or sedatives. Interactions haven’t been well studied and drowsiness can add up. Ask a pharmacist first, and never change prescribed medicine without advice.
• Diabetes or blood pressure medicines, immunosuppressants or anti-seizure medicines. These may interact. The same goes for thyroid medicines such as levothyroxine. If you take any regular medicine, ask your GP or pharmacist first, and never stop a prescribed medicine to try a supplement.
• Surgery coming up, or hormone-sensitive prostate cancer.
• Under 18s. Don’t give ashwagandha to children or teenagers for anxiety. Our products are for adults only.

What UK and European regulators say about ashwagandha

Ashwagandha is legal to sell as a food supplement in the UK, but several regulators have become more cautious since 2023. Positions checked on 30 October 2026:

A 2026 review argues that much of the European concern lumps root and leaf products together, which is another reason to choose a root extract. Our UK ashwagandha safety review tracks each change.

When to get help for anxiety

See a GP if worry is hard to control, lasts for weeks, or affects your sleep, work or relationships. Adults in England can also refer themselves to NHS Talking Therapies without seeing a GP first. If you’re not sure whether what you feel is anxiety, our guide to anxiety symptoms may help.

Related guides

• Comparing gentler options? Our guide to L-theanine covers what 31 trials found.
• Lion’s mane and reishi for anxiety.
• Weighing up CBD instead? Read what the research says about CBD and anxiety.
• Coping on the outside but anxious underneath? See high-functioning anxiety.
• See also our UK guide to lowering cortisol naturally, including what raises it in the first place.
• For a full breakdown by extract, see how much ashwagandha per day, including KSM-66 and powder doses.
• Buying on the high street? See Holland and Barrett ashwagandha: KSM-66, strengths and UK safety.
• Many of these trials used one branded root extract: see what KSM-66 is and how it differs from Sensoril and Shoden.
• Changes in these trials took weeks, not hours: see how long ashwagandha takes to work.
• If you’re looking at CBD oils that contain ashwagandha, our best CBD oil for anxiety UK guide explains what to check first and who should skip ashwagandha.