Can Ashwagandha Make You Sleepy?
Yes, ashwagandha has sedative properties and can cause sleepiness, particularly when used at doses of 300-600 mg daily. 1
Sedative Mechanism and Effects
Ashwagandha (Withania somnifera) functions as a sedative agent independent of other medications, meaning it has inherent sleep-promoting properties. 1 The herb appears to work through multiple pathways:
- Direct sedative action: Ashwagandha exhibits sleep-inducing potential that can improve sleep onset latency (the time it takes to fall asleep). 2
- Anxiety reduction: By reducing stress and anxiety levels, ashwagandha indirectly promotes sleepiness and better sleep quality. 3
Clinical Evidence for Sleep-Inducing Effects
The most robust evidence comes from recent randomized controlled trials demonstrating significant sleep improvements:
- At 300 mg twice daily (600 mg/day): Ashwagandha significantly shortened sleep onset latency to 29 minutes compared to 33.94 minutes with placebo after 10 weeks of treatment. 2
- Sleep efficiency improvements: Sleep efficiency increased from 75.63% at baseline to 83.48% after 10 weeks with ashwagandha treatment. 2
- Meta-analysis findings: A 2021 systematic review of 5 randomized controlled trials (400 participants) found ashwagandha extract had a small but significant effect on overall sleep, with effects most prominent at doses ≥600 mg/day and treatment duration ≥8 weeks. 4
Dose-Response Relationship
The sedative effects appear dose-dependent:
- Lower doses (250 mg/day): Showed modest improvements in stress and sleep quality. 3
- Higher doses (600 mg/day): Demonstrated more pronounced effects on sleep parameters, particularly in individuals with insomnia. 3, 5
- Insomnia patients: Experience more significant improvements compared to healthy individuals at the same doses. 5
Clinical Implications and Timing Considerations
When ashwagandha causes sleepiness matters for safety:
- The sedative properties can be problematic if taken before activities requiring alertness (driving, operating machinery). 1
- Anesthesia interactions: Ashwagandha's sedative effects can potentiate anesthetic medications, making perioperative cessation advisable. 1
- The sleep-promoting effects are generally well-tolerated with no serious adverse effects reported in clinical trials. 2, 4
Practical Recommendations
For patients asking about ashwagandha's sedative effects:
- Expect sleepiness: Particularly at therapeutic doses (300-600 mg daily), sleepiness is an intended effect when used for sleep disorders. 2, 5
- Timing matters: Take ashwagandha in the evening if using it for sleep improvement, or be cautious about daytime activities requiring alertness. 1
- Individual variation: While clinical trials show consistent sleep-promoting effects, the degree of sleepiness varies among individuals. 5
- Duration of effect: Maximal sleep benefits typically emerge after 8-10 weeks of consistent use. 2, 4