How long does ashwagandha take to work? What research says
Short answer: There is no fixed timeframe. In studies of ashwagandha extract, the differences from placebo were usually measured after 6 to 10 weeks. After 4 to 5 weeks they were still small or not detectable, and the placebo groups improved too. So research gives no basis for expecting anything after a few days. Do watch for side effects in the first weeks, though: in case reports, liver problems linked to ashwagandha appeared after 2 to 12 weeks.
Last updated: 5 November 2026 · Written by Florian Fermin
"How fast does ashwagandha work?" is one of the questions we get most often. At GOYU we sell ashwagandha as KSM-66 capsules, capsules with ground root and powder. Even so, we won't promise you a timeframe here, because there isn't one. What we can show you: how long the studies lasted, when researchers took measurements and what they saw at that point. What ashwagandha (Withania somnifera) is and what is being studied, you can read in ashwagandha: effects and KSM-66.
How fast does ashwagandha work according to research?
In most studies, the first clear difference from placebo was only measured at the end, after 6 to 10 weeks. Studies that also measured halfway saw no clear difference from placebo yet after 4 to 5 weeks. A review of five sleep studies found larger differences in studies lasting 8 weeks or longer and at 600 mg of extract or more per day (Cheah et al., 2021).
That doesn't mean you will feel different after exactly 8 weeks. It only means that researchers usually measured after a number of weeks, and that little is known about the first days and weeks.
How long did the studies on ashwagandha last?
| Study | Who | How much extract per day | Duration and measurement points | What did they see? |
|---|---|---|---|---|
| Salve et al., 2019 | 60 healthy adults with high perceived stress | 250 or 600 mg root extract | 8 weeks; measured after 4 and 8 weeks | After 4 weeks, stress scores were lower in all groups, placebo included, and the difference was still small. After 8 weeks the difference from placebo was statistically clear |
| Langade et al., 2019 | 60 people with insomnia and anxiety symptoms | 300 mg root extract twice a day | 10 weeks; measured after 5 and 10 weeks | The time to fall asleep got shorter in both groups. Only after 10 weeks was it clearly shorter in the ashwagandha group than with placebo |
| Deshpande et al., 2020 | 150 healthy adults who didn't wake up feeling rested | 120 mg extract | 6 weeks | After 6 weeks, people's own rating of their sleep quality was 72% higher, compared with 29% on placebo |
| Chandrasekhar et al., 2012 | 64 adults with long-term stress | 300 mg root extract twice a day | 60 days; measured at the start and end | After 60 days, lower scores on stress questionnaires and lower cortisol than with placebo |
| Lopresti et al., 2019 | 60 adults with high perceived stress | 240 mg extract | 60 days; measured at the start and end | After 60 days, a lower anxiety score than with placebo; on a second questionnaire the difference was not clear |
Keep in mind: these are small studies, mostly from India, each with a different extract and a different dose. What these studies show is what researchers measured in those groups. It doesn't tell you what you will notice.
Why did the placebo group improve too?
In almost all studies, scores also improved in the people who got a dummy capsule. In Salve's stress study, the stress score in the placebo group fell from 22.7 to 16.6 in 8 weeks; in the ashwagandha groups to 15.0 and 14.2. In Deshpande's sleep study, people's own rating of their sleep improved by 29% on placebo.
That can have several causes: simply taking part in a study, paying attention to it and taking something at set times can change scores. So if you notice something in the first few days, you don't know whether it's down to ashwagandha.
Do the dose or the form matter?
The studies used extracts of 120 to 600 mg per day. The differences from placebo were larger in the sleep studies at 600 mg or more (Cheah et al., 2021). So don't take more than the label says to make it go "faster": there is no more research on higher doses and longer use, and the daily dose on the label is the limit.
| Product | What's in it? | Daily dose on our label |
|---|---|---|
| Ashwagandha KSM-66 capsules | 500 mg root extract per capsule | 1 capsule per day |
| Ashwagandha capsules 500 mg | 500 mg ground root per capsule | 1 capsule per day |
| Ashwagandha powder | Ground root | 1 scoop (about 1 gram) per day |
Ground root is not the same as an extract: the studies above used extracts, so you can't apply the results one to one to powder or capsules with ground root. How to use the powder, you can read in how to use ashwagandha powder. All the forms are compared in ashwagandha capsules, tablets or powder.
How long can you take ashwagandha?
That is not well known. Most studies lasted 6 to 12 weeks. The review by Cheah concludes that there is too little data to say whether long-term use is safe. If you take ashwagandha every day for longer than a few months, talk to your doctor about it.
Also be aware that the Dutch National Institute for Public Health and the Environment (RIVM) advises, as a precaution, not to use herbal preparations with ashwagandha, especially during pregnancy (RIVM, 2024), and that the German Federal Institute for Risk Assessment (BfR) advises against food supplements with ashwagandha (BfR, 2024). In the EU, ashwagandha in food supplements is not considered a novel food (Novel Food Catalogue), and in France it is permitted with the five mandatory warnings below.
What complaints can occur in the first weeks?
In the studies, side effects were usually mild and occurred about as often as with placebo (Chandrasekhar et al., 2012). Rare, but serious, is liver injury. Doctors in Iceland and the US described five people who developed yellow skin and itching, and felt nauseous and tired, 2 to 12 weeks after starting ashwagandha. In four of them, liver values recovered within 1 to 5 months (Björnsson et al., 2020). In 2023 the Netherlands Pharmacovigilance Centre Lareb received four reports of liver injury with products containing ashwagandha (Lareb, 2023).
So side effects can also appear in exactly the period in which you might be waiting for an effect. Do you get yellow skin or yellow eyes, itching, nausea or stomach pain? Then stop and contact your doctor. According to the mandatory French warnings, ashwagandha is also not recommended when driving or operating machinery (Compl'Alim).
Who is ashwagandha not suitable for?
Ashwagandha is not recommended during pregnancy and breastfeeding, under 18, with hormonal, liver or heart disorders, or when driving or combining it with substances that depress the nervous system. These are the five warnings the French government makes mandatory for food supplements with ashwagandha (Compl'Alim):
- Not recommended for pregnant or breastfeeding women.
- Not recommended for people under 18 years of age.
- Not recommended for people with endocrine disorders (particularly thyroid disorders and hyperandrogenism).
- Not recommended for people with liver or heart disorders.
- Not recommended when driving vehicles or operating machinery and/or in combination with substances that depress the central nervous system.
If you take medication, especially sleeping pills, sedatives or thyroid medication, check with your doctor or pharmacist first. What else to look for when choosing a product, you can read in buying ashwagandha: what to look for.
Summary in 3 points
- There is no fixed timeframe. In studies, the difference from placebo was usually measured after 6 to 10 weeks; after 4 to 5 weeks it was still small or not detectable.
- The placebo groups improved too. So what you notice in the first few days may also have other causes.
- Don't take more than the label says, don't use it for longer than a few months without checking with your doctor, and stop if you get complaints such as yellow skin, itching or nausea.
Frequently asked questions
Does ashwagandha work straight away?
There is no research showing that. The studies measured after weeks, not after hours or days. After 4 to 5 weeks the difference from placebo was still small or not detectable.
How long does it take for ashwagandha to do something for your sleep?
That's impossible to say. The sleep studies lasted 6 to 10 weeks. In Langade's study, the time to fall asleep got shorter in both groups, and the difference from placebo was only clear after 10 weeks.
Do you have to take ashwagandha every day?
In the studies, participants took it every day. Our label also gives a daily dose: 1 capsule or 1 scoop per day, with or right after a meal.
Can I take more so it works faster?
No. Don't exceed the daily dose on the label. There is no research showing that a higher dose works faster, and little is known about the safety of higher doses.
How long can I take ashwagandha in a row?
That is not known; most studies lasted 6 to 12 weeks. If you want to take it for longer than a few months, check with your doctor.
Sources
- Salve J, Pate S, Debnath K, Langade D. Randomised, double-blind, placebo-controlled study with 250 or 600 mg ashwagandha root extract per day in 60 healthy adults with stress, 8 weeks. Cureus. 2019;11(12):e6466. doi:10.7759/cureus.6466. PubMed 32021735
- Langade D, Kanchi S, Salve J, Debnath K, Ambegaokar D. Randomised, double-blind, placebo-controlled study with 300 mg ashwagandha root extract twice a day in 60 people with insomnia and anxiety, 10 weeks. Cureus. 2019;11(9):e5797. doi:10.7759/cureus.5797. PubMed 31728244
- Deshpande A, Irani N, Balkrishnan R, Benny IR. Randomised, double-blind, placebo-controlled study with 120 mg ashwagandha extract per day in 150 healthy adults, 6 weeks. Sleep Med. 2020;72:28-36. doi:10.1016/j.sleep.2020.03.012. PubMed 32540634
- Chandrasekhar K, Kapoor J, Anishetty S. Randomised, placebo-controlled study with 300 mg ashwagandha root extract twice daily in 64 adults, 60 days; side effects mild and comparable to placebo. Indian J Psychol Med. 2012;34(3):255-262. doi:10.4103/0253-7176.106022. PubMed 23439798
- Lopresti AL, Smith SJ, Malvi H, Kodgule R. Randomised, double-blind, placebo-controlled study with 240 mg ashwagandha extract per day in 60 adults with stress, 60 days. Medicine (Baltimore). 2019;98(37):e17186. doi:10.1097/MD.0000000000017186. PubMed 31517876
- Cheah KL, Norhayati MN, Husniati Yaacob L, Abdul Rahman R. Systematic review and meta-analysis of 5 studies (400 participants) on ashwagandha extract and sleep. PLoS One. 2021;16(9):e0257843. doi:10.1371/journal.pone.0257843. PubMed 34559859
- Björnsson HK, Björnsson ES, Avula B, et al. Case series (5 people) with liver injury after using ashwagandha, Iceland and US. Liver Int. 2020;40(4):825-829. doi:10.1111/liv.14393. PubMed 31991029
- Netherlands Pharmacovigilance Centre Lareb. Leverschade bij producten met Ashwagandha (liver injury with products containing ashwagandha), 11 September 2023. lareb.nl
- RIVM. Risk assessment of herbal preparations containing Withania somnifera (Ashwagandha). Report 2024-0029, 5 March 2024. rivm.nl
- BfR. Ashwagandha: food supplements with potential health risks. Communication 39/2024, 10 September 2024. bfr.bund.de (PDF)
- Compl'Alim (French government), ingredient sheet Withania somnifera (L.) Dunal: mandatory label warnings, accessed 5 November 2026. compl-alim.beta.gouv.fr
- European Commission, Novel Food Status Catalogue, entry Withania somnifera (L.) Dunal (POL-NF-00786): "not novel in food supplements", accessed 5 November 2026. ec.europa.eu
- GOYU, labels and product pages of Ashwagandha KSM-66 Capsules, Ashwagandha Capsules 500 mg and Ashwagandha Powder (directions for use and warnings), accessed 5 November 2026.
You'll find all forms of our ashwagandha on the buy ashwagandha page.
This article is for information only and is not medical advice. Food supplements are not a substitute for a varied and balanced diet and a healthy lifestyle. If in doubt, pregnant or taking medication, check with your doctor or pharmacist.
Ashwagandha from GOYU
Organic, as KSM-66 capsules (500 mg extract), capsules with ground root and powder. With the directions for use and the warnings on the label.
