Last update
3/31/2026
Reviewed By
Overview
SCIENTIFIC SCORE
Likely Ineffective
Based on 2 Researches
4
USERS' SCORE
Moderately Good
Based on 23 Reviews
7.7
Supplement Facts
Serving Size: 1 Veg Capsule
Amount Per Serving
%DV
L-Theanine
200 mg
*
Inositol
100 mg
*
Top Medical Research Studies
4
Insufficient evidence for L-theanine
We examined the effectiveness of various sleep medications, including L-theanine, for children and adolescents with ADHD. Out of 337 articles, only five were relevant.
While L-theanine showed some improvement in sleep efficiency, it did not significantly reduce sleep latency or increase overall sleep time. Other medications like clonidine and melatonin showed more promising results, reducing insomnia more effectively.
Overall, the lack of robust evidence for L-theanine suggests that more research is needed to confirm these findings and guide treatment options.
While L-theanine showed some improvement in sleep efficiency, it did not significantly reduce sleep latency or increase overall sleep time. Other medications like clonidine and melatonin showed more promising results, reducing insomnia more effectively.
Overall, the lack of robust evidence for L-theanine suggests that more research is needed to confirm these findings and guide treatment options.
Read More
4
In our 10-week study with 46 participants diagnosed with Generalized Anxiety Disorder (GAD), we aimed to see if L-theanine could enhance sleep and reduce anxiety when combined with standard antidepressants.
While L-theanine didn’t significantly lower anxiety or insomnia severity compared to a placebo, participants on L-theanine did report feeling more satisfied with their sleep quality. Particularly, those experiencing non-clinical insomnia symptoms noted better outcomes.
These findings suggest that while L-theanine may not be a strong treatment for anxiety, it could have potential for improving sleep satisfaction.
While L-theanine didn’t significantly lower anxiety or insomnia severity compared to a placebo, participants on L-theanine did report feeling more satisfied with their sleep quality. Particularly, those experiencing non-clinical insomnia symptoms noted better outcomes.
These findings suggest that while L-theanine may not be a strong treatment for anxiety, it could have potential for improving sleep satisfaction.
Read More
Most Useful Reviews
9
Life-changing results
25 people found this helpful
It changed my life! I'd been grappling with unwarranted stress, and despite trying various methods like meditation and appropriate medication, nothing worked. I discovered L-Theanine in an ADHD forum, where some noted its helpfulness with sleep and stress. After nearly a month of taking it alongside my morning tea, the stress faded. Most importantly, my insomnia improved; I now sleep for 6.5 hours straight, a true miracle for me! I find 100 mg might suit most, as 200 mg has a significant effect on me. I'll compare the two and update later.
Read More
7.5
Helps maintain sleep
18 people found this helpful
Works wonderfully for my insomnia! Instead of relying on medications that leave me feeling groggy, I take a combination of L-Theanine and Inositol to help me drift back to sleep. I'm unsure why this supplement works better than melatonin or other options I've tried, but it certainly does. My physician suggested this supplement, and it has been effective for my sleep struggles. I trust the Now brand and would purchase it again.
Read More
8.5
Effective for insomnia
17 people found this helpful
Theanine has been great for my insomnia, lowering blood pressure and alleviating high cortisol levels. Prior to this, I struggled to find effective solutions, and my doctor wasn’t much help. After starting with Theanine in the evening, those early awakenings at 3 am, along with the discomfort and burning sensation, ceased. I also discovered that my blood pressure dropped significantly after taking it, and over time my knees felt better than they have in years. I now take it twice daily and will experiment with lower dosages more frequently.
Read More
Medical Researches
SCIENTIFIC SCORE
Likely Ineffective
Based on 2 Researches
4
- All Researches
4
In our 10-week study with 46 participants diagnosed with Generalized Anxiety Disorder (GAD), we aimed to see if L-theanine could enhance sleep and reduce anxiety when combined with standard antidepressants.
While L-theanine didn’t significantly lower anxiety or insomnia severity compared to a placebo, participants on L-theanine did report feeling more satisfied with their sleep quality. Particularly, those experiencing non-clinical insomnia symptoms noted better outcomes.
These findings suggest that while L-theanine may not be a strong treatment for anxiety, it could have potential for improving sleep satisfaction.
While L-theanine didn’t significantly lower anxiety or insomnia severity compared to a placebo, participants on L-theanine did report feeling more satisfied with their sleep quality. Particularly, those experiencing non-clinical insomnia symptoms noted better outcomes.
These findings suggest that while L-theanine may not be a strong treatment for anxiety, it could have potential for improving sleep satisfaction.
Read More
4
Insufficient evidence for L-theanine
We examined the effectiveness of various sleep medications, including L-theanine, for children and adolescents with ADHD. Out of 337 articles, only five were relevant.
While L-theanine showed some improvement in sleep efficiency, it did not significantly reduce sleep latency or increase overall sleep time. Other medications like clonidine and melatonin showed more promising results, reducing insomnia more effectively.
Overall, the lack of robust evidence for L-theanine suggests that more research is needed to confirm these findings and guide treatment options.
While L-theanine showed some improvement in sleep efficiency, it did not significantly reduce sleep latency or increase overall sleep time. Other medications like clonidine and melatonin showed more promising results, reducing insomnia more effectively.
Overall, the lack of robust evidence for L-theanine suggests that more research is needed to confirm these findings and guide treatment options.
Read More
User Reviews
USERS' SCORE
Moderately Good
Based on 23 Reviews
7.7
- All Reviews
- Positive Reviews
- Negative Reviews
9
Life-changing results
25 people found this helpful
It changed my life! I'd been grappling with unwarranted stress, and despite trying various methods like meditation and appropriate medication, nothing worked. I discovered L-Theanine in an ADHD forum, where some noted its helpfulness with sleep and stress. After nearly a month of taking it alongside my morning tea, the stress faded. Most importantly, my insomnia improved; I now sleep for 6.5 hours straight, a true miracle for me! I find 100 mg might suit most, as 200 mg has a significant effect on me. I'll compare the two and update later.
Read More
7.5
Helps maintain sleep
18 people found this helpful
Works wonderfully for my insomnia! Instead of relying on medications that leave me feeling groggy, I take a combination of L-Theanine and Inositol to help me drift back to sleep. I'm unsure why this supplement works better than melatonin or other options I've tried, but it certainly does. My physician suggested this supplement, and it has been effective for my sleep struggles. I trust the Now brand and would purchase it again.
Read More
8.5
Effective for insomnia
17 people found this helpful
Theanine has been great for my insomnia, lowering blood pressure and alleviating high cortisol levels. Prior to this, I struggled to find effective solutions, and my doctor wasn’t much help. After starting with Theanine in the evening, those early awakenings at 3 am, along with the discomfort and burning sensation, ceased. I also discovered that my blood pressure dropped significantly after taking it, and over time my knees felt better than they have in years. I now take it twice daily and will experiment with lower dosages more frequently.
Read More
0
Unwanted effects
6 people found this helpful
A futile purchase for me. L-theanine creates strong and unnecessary excitation in my nervous system, resulting in insomnia, regardless of my dosage attempts.
Read More
9
Essential supplement
2 people found this helpful
To combat insomnia, I used to struggle with sleep and waking frequently at night. Since taking this, along with glycine and GABA before bed, I've been able to fall asleep more easily and stay asleep longer. It's become one of my essential supplements.
Read More
Frequently Asked Questions
9
Essential supplement
2 people found this helpful
To combat insomnia, I used to struggle with sleep and waking frequently at night. Since taking this, along with glycine and GABA before bed, I've been able to fall asleep more easily and stay asleep longer. It's become one of my essential supplements.
0
Unwanted effects
6 people found this helpful
A futile purchase for me. L-theanine creates strong and unnecessary excitation in my nervous system, resulting in insomnia, regardless of my dosage attempts.
4
In our 10-week study with 46 participants diagnosed with Generalized Anxiety Disorder (GAD), we aimed to see if L-theanine could enhance sleep and reduce anxiety when combined with standard antidepressants.
While L-theanine didn’t significantly lower anxiety or insomnia severity compared to a placebo, participants on L-theanine did report feeling more satisfied with their sleep quality. Particularly, those experiencing non-clinical insomnia symptoms noted better outcomes.
These findings suggest that while L-theanine may not be a strong treatment for anxiety, it could have potential for improving sleep satisfaction.
While L-theanine didn’t significantly lower anxiety or insomnia severity compared to a placebo, participants on L-theanine did report feeling more satisfied with their sleep quality. Particularly, those experiencing non-clinical insomnia symptoms noted better outcomes.
These findings suggest that while L-theanine may not be a strong treatment for anxiety, it could have potential for improving sleep satisfaction.
4
Insufficient evidence for L-theanine
We examined the effectiveness of various sleep medications, including L-theanine, for children and adolescents with ADHD. Out of 337 articles, only five were relevant.
While L-theanine showed some improvement in sleep efficiency, it did not significantly reduce sleep latency or increase overall sleep time. Other medications like clonidine and melatonin showed more promising results, reducing insomnia more effectively.
Overall, the lack of robust evidence for L-theanine suggests that more research is needed to confirm these findings and guide treatment options.
While L-theanine showed some improvement in sleep efficiency, it did not significantly reduce sleep latency or increase overall sleep time. Other medications like clonidine and melatonin showed more promising results, reducing insomnia more effectively.
Overall, the lack of robust evidence for L-theanine suggests that more research is needed to confirm these findings and guide treatment options.
References
- Sarris J, Byrne GJ, Cribb L, Oliver G, Murphy J, et al. L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled trial. J Psychiatr Res. 2019;110:31. 10.1016/j.jpsychires.2018.12.014
- Barrett JR, Tracy DK, Giaroli G. To sleep or not to sleep: a systematic review of the literature of pharmacological treatments of insomnia in children and adolescents with attention-deficit/hyperactivity disorder. J Child Adolesc Psychopharmacol. 2013;23:640. 10.1089/cap.2013.0059
