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User Reviews for L-theanine to treat Dietary Supplementation

L-theanine has an average rating of 5.4 out of 10 from a total of 97 ratings for the treatment of Dietary Supplementation. 47% of those users who reviewed L-theanine reported a positive effect, while 47% reported a negative effect.

L-theanine Rating Summary

5.4/10 average rating

97 ratings from 99 user reviews.

Compare all 215 medications used in the treatment of Dietary Supplementation.

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Reviews for L-theanine

Aaronedwards2012 · Taken for 1 to 6 months May 21, 2021

“I buy the powdered ltheanine which is better as it is pure and does not have any other ingredients in it i put it under my tongue and the effects are almost immediate and calming as it goes straight into the blood stream then swallow the rest”

10 / 10
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clarkmccray2 · Taken for 1 to 6 months May 14, 2021

“I am a 52 year old average size (5'10", 180lbs) male. I suffer from severe depression, anxiety with panic attacks and agoraphobia. Medications given by my psychiatrist only stabilize me to be functional. THEN I found L-Theanine. When my anxiety begins rising toward a panic attack (throwing my mood deeper into depression), I take 200mg of L-Theanine. Within 45 minutes I just notice "hey, no panic attack yet" and "I feel so calm". If I still feel a bit anxious after 45 minutes, I take another 200mg. I take 200mg before I leave my home. It doesn't make me tired, but does give me a relaxed sleep. The only side affects I have noticed are sometimes a slight headache and moderate nausea if I take on an empty stomach. I prefer it over Rx meds to avoid the dizziness and chance of addiction. L-Theanine has dramatically improved my quality of life. It is my lifesavor!”

10 / 10
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jiveclive · Taken for 2 to 5 years April 27, 2021

“I've been using this for years.The first to counter glutamate sensitivity or reactions which it does very well. I've used it to relax but (for me) it lasted to long. I felt my most relaxed and tired about 8 hours after I took it so I assume it has a long half-life. It's not something to chill you for 2 or 3 hours. For the last 9 months or so I been using it a help sleep. Just 100mg a few hours before bed helps but doesn't keep me asleep for more than 4 hours. I find adding anything to this like melotonin or inositol to improve sleep just causes side effects. In fact just the L-Theanine alone after 8 months or so of use started to cause all day dizziness and headaches that made me have to stop using it. I keep it now in case I eat something dining out that's very high in glutamate (like seafood) or has unlabeled MSG as I do get reactions like elevated BP and pulse which this definitely helps with. Great for occasional use.”

8 / 10
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lisamueller · Taken for less than 1 month March 7, 2021

“I got horrible chest pain and tachycardia (fast heart beats) and palpitations from just 50 mg.’s every time I took it. I haven’t found any warnings of these side effects for this until I came on here. This site is so helpful. Be very careful with this supplement. Start very low and look out for worsening mood and anxiety. I can’t believe no other websites list these common side effects.”

1 / 10
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T · Taken for 1 to 6 months December 18, 2019

“l-theanine is awesome stuff that I've used for ADHD/anxiety a while. I'm off all ADHD and anxiety meds. Let me correct a few things I've seen in other reviews. #1 it is NOT a drug. L-theanine is simply an amino acid. #2 it does react strongly with coffee and caffeine. Just be aware. #3 figure out your dose. It is not a prescription medication. Often it's suggested to take 100 mg twice a day. That is just a suggestion. I had side effects so I just lowered the dose. I adjusted down because of my metabolism. I take. I only take 50 mg a day. I'm 6 foot all and over 200lbs. I get the chance tabs so I can break them in half. Works like a charm.”

8 / 10
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jasonl62 · Taken for less than 1 month November 13, 2019

“I was looking for something that would help calm my brain down so I could stop over thinking about things, all in all without prescription drugs. I stumbled across L-Theanine in walmart, so I decided to give it a try. As soon as I took it, about an hour later I felt like I had my peace of mind back. I wasn't stressed or anxious and it gave me my motivation back. I don't think it was a placebo effect because I haven't felt this way in a long time. I noticed in a lot of reports that people take it for sleep but I feel it has the opposite effect with me. I feel like it gives me energy and motivation to get things done. I take like 200mg at a time about twice a day. In a way it kind of gives me a euphoric feeling, but not the type that is induced by prescription drugs. It's hard to explain but it's more like a clear, peace of mind, dreamy, motivational type of state. L-Theanine is a miracle supplement as it helps out with a bunch of my mental/anxiety issues all at once.”

9 / 10
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Lrm · Taken for 1 to 6 months January 25, 2021

“Using L theanine is my final step in curing myself from the terrible side effects of benzodiazepines. I worked long and hard to get off of 15 years use of benzodiazepines when I became intolerant 4 years ago. I now use L theanine 200 mg four to five times per day in life is good.”

10 / 10
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Only Natural · Taken for 1 to 2 years October 17, 2020

“I was diagnosed with anxiety about a year and a half ago and refuse to take prescription medication due to the long term side effects. I did hours and hours of research to find something that helped. I found L-Theanine, which is NOT a drug as some have mentioned, and have experienced nothing but relief. For those with anxiety still drinking caffeine and still having anxiety/panic kick the caffeine out of your life!! I'd have all day anxiety and insomnia but after taking 100mgs of L-Theanine 3 times per day I have felt much better without taking a drug. Give this a try, its not a drug.”

10 / 10
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Robin1961 · Taken for less than 1 month January 12, 2014

“I am a 53 year old female and have ADD. For almost 1 year, I was having extremely difficult memory problems. There weren't enough Post-it notes in the world to help relieve my anxiety about my progressing memory problem. The biggest result I have had is the ability to focus on my work, assimilate information and stay on task. I've taken prescribed medications (Ritalin, Xanax) in an effort to correct my mild ADD. This supplement is a life-saver, and job-saver for me.”

9 / 10
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Anonymous · Taken for less than 1 month March 8, 2021

“I took l-theanine combined with melatonin to help me fall sleep and my experience was awful. It made me almost jittery, and although I was very tired, I couldn’t go to sleep because of the restlessness it caused. Once I did fall asleep I woke up frequently feeling really anxious.”

1 / 10
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Chloey17 November 15, 2019

“I started taking L-Theanine about 3 months ago and I think at first I felt it helped my sleep. The last month has been horrendous. I literally would wake up 6-8 times a night wide awake. Sometimes even felt extremely anxious like a panic attack was coming on. I was wide awake all night long then exhausted the day after. Averaging 3-4 hours of restless sleep every night. I was getting extremely worried about what was happening to me. I was running low on my pills and about to order another bottle but decided to research L-theanine a little more first and saw other people having similar side effects so I immediately stopped taking them which was 3 days ago. The last 2 nights I slept soooooo much better. No more waking up 8 times a night in a panic. I also have the MTHFR gene mutation which may be the reason why it has the opposite effect on me. L-theanine increases GABA levels which has opposite effect on those of us with the MTHFR gene mutation. My bottle is going in the trash!”

1 / 10
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Ahab888 April 3, 2017

“I have been having roughly 4 panic attacks daily for a month. I hate pharm. drugs so I tried this. Worked immediately!!!!! Within 20 mins I felt like I've never had anxiety in my life. This supplement is great!”

10 / 10
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NateTGreat · Taken for less than 1 month September 28, 2016

“I have ptsd, generalized anxiety, and panic disorder from years of substance abuse which effect many facets of my health. I cannot handle stress well, my head is usually pulsing or aching, and I frequently get dizzy spells and feel lightheaded. I tried lexapro and it did not really make me feel well. It helped with anxiety and the panic attacks, but I felt emotionally flat and withdrawn from life. Since stopping the lexapro, I have resumed many of my previous daily symptoms associated with anxiety. I just started taking a liquid concentrate of l-theanine sublingually and it is nothing short of a miracle. My head is clear again and I can actually deal with my responsibilities. I feel like my life was given back to me. Highly recommended.”

10 / 10
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Autism Mom · Taken for less than 1 month June 25, 2016

“I purchased this product a few days ago because it's a safe alternative to ssri'so for my son's anxiety. He's on the autism spectrum, he's 13 with severe anxiety. I have been giving him a hundred milligrams 3 times a day and he told me how much better he feels, he's so much happier. He isn't easily distracted or buried in video games. He's talkative and his conversations are appropriate. So far I think this is a miracle drug. I really hope this continues.”

10 / 10
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TT August 28, 2016

“I have been perscibed just about every drug (Chemical) they have for anxiety and depression, after finding out about the benefits of L-Theanine I have been taking 200mg per day and I feel like I did before I knew depression ever existed! Amazingly my body is reacting very well to the supplement and has not experienced a withdrawal effect from no longer taking the xanax I love that its all natural it's like brain food I feel so Alive”

10 / 10
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Brian new man February 24, 2017

“I've always been a kind of anxious person but after years of alcohol abuse my anxiety hit the roof. I had anxiety for months on end and could find no relief. Eventually I had to start working out three times a day to actually get relief from anxiety. After days and days of researching I finally stumbled upon green tea and how can relax you. I started drinking gallons of green tea every day and start feeling a little bit less anxious. After a few weeks of doing this I decided to look into why green tea helped and found out it was L-theanine. I took these pills three times a day for three months and was finally able to breathe again. Greatest discovery ever!!! I highly recommend trying them.”

10 / 10
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Pat206 July 23, 2017

“Anxiety was so bad, [e.g.] I'd start to peel an onion, but was FRIGHTENED that I couldn't finish, so felt incapable of making the WHOLE meal! Mental fear about everything!! NOTE: I didn't eat healthy, nor was I motivated to exercise. I was on medication for app. 10 years but didn't want to forever. Tried natural remedies and mind exercises, but didn't do much for me. Then heard of L-THEANINE, researched, and bought some. 1 tab. p/d for 7-10+ days, before a tiny 'glimmer' of hope. Now 2 months later I feel okay -occasional bad day. I'm eating healthy now and exercising, which together, can HELP anxiety. L-theanine got me feeling well enough to take care of myself. I really hope it can kick-start you too, into getting better.♥ Pat”

10 / 10
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Dizz79 July 25, 2016

“Military Veteran suffering from ptsd, anxiety, and insomnia. I was skeptical at first, after taking 400mg per day I definitely notice a difference. Not a miracle happy pill, but takes the edge away, allows me to feel halfway normal in stressful situations. Helps take my stomach out of knots. Sleep a little better. Can't complain, will continue to take.”

8 / 10
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Goatmom · Taken for 1 to 6 months January 29, 2019

“Have been taking Xanax for sudden anxiety attacks for years but decided to try L-Theanine and have had very good results. I take 200 mgs 3x a day and am impressed with how well it works. Just to feel a calmness and helps me think clearly. I can focus and it stops the shaky hands and panic breathing. Also getting much much better sleep..was waking up every 2 hours with feeling of "dread"...no more. It did take about week of regular dosing to find my appropriate dose and get steady effect. I am glad I found it.”

8 / 10
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DeRee · Taken for less than 1 month May 8, 2020

“I can truly appreciate this SUPPLEMENT not prescription to clarify. I’ve been taken this supplement for about a month. I refused to get hooked on Benzos anti anxiety meds so I researched and found that this was a much better fit. I had no side effects just relaxation at bedtime which is when I take it 100mg along with 400mg of Magnesium only at bedtime because you will be ready to sleep after taking it. I was experiencing anxiety and this helped me a great deal I have even recommended it to others of course if their physician gives the green light as mine did. It crosses the brain blood barrier and that’s what I needed.”

9 / 10
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Tedu53 · Taken for 6 months to 1 year September 24, 2018

“I am an adult male with generalized anxiety disorder, I have taken benzos and antidepressants but the side effects were not worth it. L-Theanine, while mild, is effective in reducing my anxiety and stress enough for me to not feel miserable every day and it also helps me sleep. I have never experienced a negative side effect from it and I have been taking it almost daily for several months.”

8 / 10
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billy · Taken for 1 to 6 months January 28, 2021

“I tried this when my doctor recommended it for my chronic insomnia, 100mg. I find it has the opposite effect. While it relaxes you it makes you mind very aware and focused, too much so to sleep. I woke many times in the night and after a few nights I just didn't sleep. While I did not have rapid heart beats like many have reported on here I did have substantially elevated blood pressure about 5 or 6 hours after taking the pill (every time). I'm wondering how many of those reporting pounding heart beat also had high BP but didn't have a BP reader? I know generally doctors doesn't love you taking amino acids individually because your not getting a natural product in a small proportional dose. l theanine is not something I'd take again. Anything that effects your brain chemistry you need to be cautious with.”

3 / 10
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Corky · Taken for 1 to 6 months May 11, 2020

“I have Cushing disease and experience most days some anxiety, some days extreme anxiety and rarely no anxiety. I call the no anxiety days the " old me". While I have been using a combination of homeopathic, allopathic and herbal to control my anxiety, finding L-theanine felt heaven sent. I wasn't just anxious free, I felt calm, in control and even when I had an adrenal /Cushing cycle the cycle was easily handled and recovery was quick. I was me again. Then my blood pressure started to experience unusual rapid drops. From 140/80 to 78/52. I am not sure if it is the L-theanine. I was taking 225mg a day. So I have decided not to take it for a week. See what happens.”

10 / 10
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Anonymous · Taken for less than 1 month May 19, 2017

“Been recently suffering from anxiety attacks and don't want to use prescription meds so tried this out since it states no drowsiness! I've been taking it for 2 weeks now in the morning when I wake up and in the evening before bed. It has been great in calming me down and decreasing my shortness of breath! It takes about 15-20 minutes for it to start working for me. I will be taking this as a supplement from now on since it helps me to be alert and focused.”

10 / 10
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Jinx342 April 1, 2019

“I have had to rely on Xanax for the past 25 years, plus a beta blocker to fall asleep and stay asleep due to most likely an inherited genetic condition. However, in the past few weeks I’ve started taking L-theanine 100mg capsules) in the evenings after dinner to see if I could lower the intake of Xanax and/or not experience wakefulness in the very early morning hours (between 3am - 5 am). I started at the recommended dose of 100-200 mg and by the fourth day I took 600 mg - on the day that I took the 600 mg after dinner and before I take my beta blocker, I noticed a difference in my relaxation. Furthermore, I am taking 25% less Xanax. I slept very soundly through the night - also backed up by my smart watch sleep monitor - which indicated a 4.5-5.0 on the sleep quality scale (5 pt scale). I will continue to take the 600mg after dinner to help with my sleep disorder. I would love to be off benzodiazepines or at least lowering my dose by 50-75%.”

9 / 10
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Kiwik · Taken for 2 to 5 years September 6, 2015

“I take about 800 mg of L-theanine appx 1/2 hour before skating competitions to reduce my stage-fright/performance anxiety. I have also taken it before presentations at work. It works amazing well at eliminating my anxiety and allowing me to focus so that I can utilize all my practice and preparation (without being hindered by anxiety). The other benefit of L-theanine is that it doesn't make me drowsy. My Naturopath first prescribed it and now I just buy it”

9 / 10
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lifeisbutadream · Taken for less than 1 month September 24, 2020

“I write this, as I was searching for adverse effects from l-theanine. Well, lo and behold, I see others on there have also experienced dizziness and strange symptoms. I currently take 1mg. of Klonopin and 50mg. of Zoloft daily. I decided to try 200 mgs. of l-theanine last night. My hands are still shaky as I type this almost 24 hours later. I was unable to leave my house today, due to dizziness, exhaustion, depression and anxiety. When I woke up last night to go to the bathroom, I felt like the room was spinning and I awoke from a coma. I can only conclude that the l-theanine reduced my blood pressure to near zero. There were no indications that I could not take it on the medications I am on. Well, guess what? IT HAD A VERY BAD ONE ! Those of you on medications, be very cautious !!!!”

1 / 10
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Aidan · Taken for less than 1 month November 6, 2019

“Began taking l-theanine before bed for about a week— just enough time for it to really exhibit effects — forgot about it for 1-2 days and started again. When I started again I experienced a large spike in anxiety compared to usual. Felt spacey, anxious, frustrated, and even violent. I am not diagnosed with any anxiety disorders but definitely experience occasional anxiety especially in social settings and when trying to sleep.... after reading a plethora of reviews the bottom line is this: this medication is sketchy... it’s not well studied and the physiological mechanisms are not well outlined in literature. I’m a biochemistry major at strong institution so I’m not out of my element with this statement.... consult a psychiatrist before starting a dosage regimen. Hope this helps.”

2 / 10
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This information is NOT intended to endorse any particular medication. While these reviews might be helpful, they are not a substitute for the expertise, knowledge and judgement of healthcare practitioners.

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