Ashwagandha for Sleep: What Trials Found
What pooled reviews and trials of ashwagandha extract found for sleep and insomnia, how sleep was measured, whether morning or night matters, and the cautions that apply.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Long-lasting trouble sleeping deserves a conversation with a clinician, because it can have causes a supplement will not touch. This page describes research only. It does not tell anyone what to take or when.
Traditional use and research
Ashwagandha has long been used as a medicinal plant in traditional Ayurvedic medicine. [1] That is traditional use only for the purposes of this page. The sections below describe modern trials, which are a separate kind of evidence. For the tradition see Ashwagandha in Ayurveda and Ayurveda for sleep.What the pooled reviews found
| Review | What it pooled | What it found | Cautions |
|---|---|---|---|
| PLoS One, 2021 | 5 randomized trials of extract versus placebo, 400 participants [5] | A small but significant effect on overall sleep [5] | The effect looked larger in adults with diagnosed insomnia, in studies of 8 weeks or more, and where the daily amount was 600 mg or more; data on serious adverse effects were limited [5] |
| Human Psychopharmacology, 2024 | 5 trials, people with anxiety or insomnia [6] | Improvement in sleep onset time, total sleep time, sleep quality score (PSQI) and sleep efficiency, but not in time awake after falling asleep or time in bed [6] | The authors say larger studies are needed [6] |
Two individual trials
- Insomnia and anxiety, 10 weeks. In a trial of 60 patients (40 on extract, 20 on placebo), capsules of a root extract were given twice daily with milk or water. [3] Sleep was measured with a wrist-worn activity monitor (actigraphy) and questionnaires. [3] Sleep onset time improved in both the extract and placebo groups, and was significantly shorter after 10 weeks with the extract. [3]
- Healthy volunteers and people with insomnia, 8 weeks. A trial of 80 participants (40 healthy, 40 with insomnia) compared root extract with placebo. [4] The improvement was larger in the people with insomnia than in the healthy volunteers. [4]
Both are small. Funding was not checked for these two trials.
Does it matter whether you take it in the morning or at night?
Proper evidence not found. We searched PubMed for trials comparing morning with evening use, and for timing of ashwagandha and sleep, and found none. The trials above did not compare timing. One stress trial gave its extract once daily at night, and another gave capsules twice daily, so trials differ. [7][3] For general background see timing of adaptogens.Frequently asked questions
Does ashwagandha help you sleep?
Some root extracts improved sleep measures more than placebo in small trials, and a pooled review found a small but significant effect. [5] NCCIH says some preparations may be effective for insomnia. [1]
Is it better for people with insomnia than for good sleepers?
In one 8-week trial the improvement was larger in participants with insomnia than in healthy volunteers, and a pooled review saw larger effects in adults diagnosed with insomnia. [4][5]
Should it be taken in the morning or at night?
Proper evidence not found; we found no trial that compared times of day. Ask a clinician or pharmacist.
Can it make you drowsy?
Yes, NCCIH lists drowsiness among possible effects, and it may interact with sedatives. [1]
How long have sleep trials lasted?
The two trials described here lasted 8 and 10 weeks. [4][3] NCCIH says there is not enough information on long-term safety. [1]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Limits and uncertainty
- Sleep was measured in different ways (activity monitors, questionnaires), so results are not directly comparable. See how sleep and stress are measured.
- Amounts and extracts varied; a result for one extract does not transfer to another product, powder or tea. [1]
- Long-term safety is not known. [1]
Safety and who should ask first
Rare liver injury reports exist, and NCCIH says to avoid ashwagandha in pregnancy, not to use it while breastfeeding, and that it is not recommended before surgery or with autoimmune or thyroid disorders. [1] See side effects and liver injury reports, medicine interactions and the ashwagandha overview. For other options compared, see Ashwagandha vs magnesium, melatonin and L-theanine.
References
- NIH National Center for Complementary and Integrative Health, page last updated March 2023: Ashwagandha: Usefulness and Safety. Read 2026-10-23.
- GBIF species match, queried 2026-10-23: GBIF Backbone Taxonomy: Withania somnifera. Read 2026-10-23.
- Cureus, 2019: Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled Study. Read 2026-10-23.
- Journal of Ethnopharmacology, 2021: Clinical evaluation of the pharmacological impact of ashwagandha root extract on sleep in healthy volunteers and insomnia patients: A double-blind, randomized, parallel-group, placebo-controlled study. Read 2026-10-23.
- PLoS One, 2021: Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis. Read 2026-10-23.
- Human Psychopharmacology, 2024: Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis. Read 2026-10-23.
- Medicine (Baltimore), 2023: A standardized Ashwagandha root extract alleviates stress, anxiety, and improves quality of life in healthy adults by modulating stress hormones: results from a randomized, double-blind, placebo-controlled study. Read 2026-10-23.