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User Reviews for L-theanine

Condition Avg. Rating Reviews Compare
Dietary Supplementation  
5.1
125 reviews 640 medications

Reviews may be edited to correct grammar/spelling, or to remove inappropriate language and content. Reviews that appear to be created by parties with a vested interest are not published.

Reviews for L-theanine

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

For Dietary Supplementation: “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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jasonl62 · Taken for less than 1 month · November 13, 2019

For Dietary Supplementation: “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

For Dietary Supplementation: “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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T · Taken for 1 to 6 months · December 18, 2019

For Dietary Supplementation: “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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Robin1961 · Taken for less than 1 month · January 12, 2014

For Dietary Supplementation: “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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Only Natural · Taken for 1 to 2 years · October 17, 2020

For Dietary Supplementation: “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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NateTGreat · Taken for less than 1 month · September 28, 2016

For Dietary Supplementation: “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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Chloey17 · November 15, 2019

For Dietary Supplementation: “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

For Dietary Supplementation: “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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Autism Mom · Taken for less than 1 month · June 25, 2016

For Dietary Supplementation: “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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clarkmccray2 · Taken for 1 to 6 months · May 14, 2021

For Dietary Supplementation: “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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TT · August 28, 2016

For Dietary Supplementation: “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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Pat206 · July 23, 2017

For Dietary Supplementation: “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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Brian new man · February 24, 2017

For Dietary Supplementation: “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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Goatmom · Taken for 1 to 6 months · January 29, 2019

For Dietary Supplementation: “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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Dizz79 · July 25, 2016

For Dietary Supplementation: “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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Aidan · Taken for less than 1 month · November 6, 2019

For Dietary Supplementation: “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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Tedu53 · Taken for 6 months to 1 year · September 24, 2018

For Dietary Supplementation: “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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Kiwik · Taken for 2 to 5 years · September 6, 2015

For Dietary Supplementation: “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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Jinx342 · April 1, 2019

For Dietary Supplementation: “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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Anonymous · Taken for less than 1 month · May 19, 2017

For Dietary Supplementation: “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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Anonymous · Taken for less than 1 month · March 8, 2021

For Dietary Supplementation: “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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lifeisbutadream · Taken for less than 1 month · September 24, 2020

For Dietary Supplementation: “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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D · Taken for 1 to 6 months · March 26, 2020

For Dietary Supplementation: “I have been taking this for about a month, and only now have I started have really weird side effects. At first it seemed to be greatly helping my anxiety, and for about a week now I have had awful heart palpitations. I originally thought it was stress, but started realizing they would start back up after I took the l-theanine. I was taking 200mg - 400mg a day. I also experienced a low grade nausea, especially if I did not eat, as well as dizziness and fatigue. Pretty sure I cannot continue this. Also, when I went to the Dr, my blood pressure was very low, and it may have been due to this. I am a 31 year old female in very good health.”

2 / 10
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Restless · Taken for less than 1 month · December 26, 2019

For Dietary Supplementation: “Took this at night to help with inability to stay asleep and racing thoughts. Only took it a few times and not every night, more like once or twice a week. Thought it worked well the first night. Then noticed that when I take it, I have heart palpitations. Also have been having trouble sleeping due to burning sensation in my stomach. Realized this morning that the burning sensation and heart palpitations only happen when I take this supplement.”

2 / 10
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