Does ashwagandha make you sleepy?
Two different questions hide inside this one. Can it cause drowsiness as a side effect? And did the trials show better sleep at night? The answers come from different places, and they do not say the same thing.
contentsTwo questions in one
Key points
- Yes, it can. Drowsiness is on the official list of mild side effects.
- In sleep trials, the gains were small overall and larger in people with insomnia, at higher doses and over 8 weeks or more.
- In one 10-week trial, people took about 5 minutes less to fall asleep than on placebo.
- A review of the trials found people felt more alert on waking, not groggier.
- Most trials were small, short, run in one country and used one kind of extract. Long-term safety is unknown.
Two questions in one
People type this into a search bar for opposite reasons. Some want to know if it will knock them out at their desk. Others hope it will help them sleep at night. Those are different questions, and the evidence for each comes from a different place.
The side effect question is answered by safety summaries. The sleep question is answered by trials that measured sleep on purpose. We will take them one at a time.
Drowsiness as a side effect
The US Office of Dietary Supplements lists drowsiness among the common side effects of ashwagandha, alongside stomach upset, loose stools and nausea. It describes them as mild.[30] The National Center for Complementary and Integrative Health gives a similar list.[31]
Neither source says how often drowsiness happens, and the trials rarely broke it out. So the fair answer is: some people do feel sleepy on it, and you will not know whether you are one of them until you notice how you feel. Do not drive or operate machinery if it makes you drowsy.
What the sleep trials measured
A 2021 review pooled five randomized trials with 400 adults in total. Against placebo, ashwagandha had a small but significant effect on sleep.[32] The effect was larger in three situations:
- in people who had insomnia to start with,
- at doses of 600 mg a day or more,
- and in trials that ran for 8 weeks or longer.
That last point matters. These trials did not test a single capsule before bed and wait to see what happened. They tested daily use over weeks. Our timing guide goes into how the studies dosed it.
One trial, up close
One of the trials in that review followed 60 adults with insomnia for 10 weeks. Half took 300 mg of root extract twice a day with milk or water. Half took a placebo.[33]
chart · minutes to fall asleep, measured by a wrist sensor
Both groups fell asleep faster. One fell asleep a little faster.
Placebo, start
42 minPlacebo, week 10
34 minAshwagandha, start
42 minAshwagandha, week 10
29 min
Read the chart carefully. The placebo group improved by about 8 minutes on its own. The extra gain on ashwagandha was about 5 minutes. Sleep efficiency and a standard sleep questionnaire also improved more than on placebo, and no adverse events were reported.[33] Real, but modest, and the extract was supplied by its manufacturer.
And the next morning?
If something makes you sleepy at night, it is reasonable to worry about a heavy head the next day. The 2021 review looked at this. People taking ashwagandha reported better mental alertness on rising than those on placebo.[32]
That is encouraging, with a caveat. It is a self-rating from a handful of short trials, not a test of reaction time or driving. If you feel slow in the morning, trust that over a pooled average.
The limits of the evidence
- Small and similar. All five trials in the review were run in India, four used the same kind of branded root extract, and one was partly funded by its maker.[32]
- Short. Most trials lasted 6 to 12 weeks.[30] Safety beyond about 3 months is not known.[31]
- Extracts differ. Root, leaf, concentration and processing vary between products, so a result for one extract does not automatically carry over to another.
Before you try it
Ashwagandha may interact with sedatives and several other medicines, and it is not for everyone.[30] Read our interactions checklist first, and talk to a pharmacist or doctor if you take anything regularly.
It is also worth knowing what is behind the bad nights. A week of notes with the sleep diary, or seven quick questions in the sleep quiz, often points to something simpler first.
Read the trial, not the label.
Our free list sends one plain-English study breakdown at a time. No hype, no sales.
Sources
- NIH ODS, 2025. Ashwagandha: Is it helpful for stress, anxiety, or sleep? Fact Sheet for Health Professionals. Office of Dietary Supplements (NIH).
- NCCIH, 2023. Ashwagandha: Usefulness and Safety. National Center for Complementary and Integrative Health (NIH).
- Cheah et al., 2021. Effect of Ashwagandha (Withania somnifera) extract on sleep: a systematic review and meta-analysis. PLoS One.
- Langade et al., 2019. Efficacy and safety of Ashwagandha (Withania somnifera) root extract in insomnia and anxiety: a double-blind, randomized, placebo-controlled study. Cureus.
This article is educational and isn’t medical advice. It was written and checked by the UNWIRE™ editorial team; no clinician has reviewed it yet. UNWIRE™ is a nutrition company, and this article does not describe any product.
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