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L-theanine User Reviews & Ratings (Page 2)

L-theanine has an average rating of 5.3 out of 10 from a total of 136 reviews on Drugs.com. 46% of reviewers reported a positive experience, while 45% reported a negative experience.

Reviews for L-theanine

  • Fairy
  • March 26, 2019

For Dietary Supplementation "I started L Thianine taking 200mg morning and evening. I have early dementia, it was like switching a light bulb on in my brain, it helped so much with my memory, word finding, alertness etc. However, within a week I started getting horrendous heartburn, really bad, and, quite severe pain in my stomach and my ribs felt like I'd been kicked in my ribcage. I couldn't touch one part of my stomach, I saw my Dr and was told I had a stomach ulcer, I've never suffered from heartburn before and it's a really weird kind. I was prescribed omeprazole, but I didn't take it, I suspected the L Thianine so stopped it, after a few days the pain went and my stomach healed up. I started it again, after 3 days pains came back, to be absolutely sure I stopped again and re started after pain stopped, same again pain returned! Horrendous bad vivid dreams as well, every night and headaches by day."

1 / 10
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69 Report
  • Shannan
  • February 21, 2017

For Dietary Supplementation "I started taking this about two weeks ago for insomnia. It was combined with lavender oil as a natural sleep aid. It works for helping me to shut my brain off at night and fall asleep, but it caused severe dizzy spells and bad headaches. I also had some stomach upset. I hear that's a rare reaction, but just wanted users to be aware of the possibility. Today I had a dizzy spell so bad in the kitchen that I fell and hurt my hip. I am a 37 year old woman."

4 / 10
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87 Report
  • SteveO
  • Taken for 1 to 6 months
  • November 7, 2014

For Dietary Supplementation "I take L-Theanine Stress Formula with Calming Blend by Sundown. It greatly helps me relax at night time. It is not like taking a benzodiazipine, but definitely helps take the edge off. I am prescribed Adderall for trouble concentrating. I sometimes use it with the Adderall to decrease jitteryness. I also often mix L-Theanine with Valerian (whole root, not extract) to help me sleep."

9 / 10
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95 Report
  • Carl
  • Taken for less than 1 month
  • April 29, 2020

For Dietary Supplementation "I started theanine last week. It seemed great the first few days. Then these past 2 days it has triggered some really nasty anxiety attacks. I was up until 3am afraid to go to sleep for 2 nights in a row. It causes extreme thirst and hard and heavy heartbeats. I believe this drops my blood pressure too low in conjunction with propranolol. Will not take again. Be careful with this stuff."

2 / 10
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48 Report
  • Corky
  • Taken for 1 to 6 months
  • May 11, 2020

For Dietary Supplementation "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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47 Report

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  • Shutt...
  • Taken for less than 1 month
  • October 29, 2016

For Dietary Supplementation "I have trouble turning off my brain as soon as the lights go off at bed time. I some times get only 4 hours of sleep. This melatonin plus 200gm L-theanime is helping me go to sleep and stay asleep. I am type 2 Diebetic and I have also noticed my blood sugar levels are much better."

10 / 10
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75 Report
  • Myles
  • February 18, 2019

For Dietary Supplementation "Honestly this really isn’t as great as it seems. Yeah it will do it’s job and relax you, but to the point you start forgetting stuff. Being in weird moods. Your appetite will be different. Also my stomach has just been feeling full and heart burn happens easier then it did before. If I drink a beer or 2 it just feels like I’m so full and get a weird as feeling. Also makes you have even worse anxiety after you take it. As if it makes you feel okay but when it wears off or you don’t take it. You feel crazy. A tleast I did. I will no longer take this. I don’t recommend it, unless you want to feel not like your self. Don’t let it make you feel this is a thing that doesn’t have side effects because it does."

2 / 10
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57 Report
  • DeRee
  • Taken for less than 1 month
  • May 8, 2020

For Dietary Supplementation "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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45 Report
  • Joey
  • Taken for 1 to 6 months
  • August 1, 2019

For Dietary Supplementation "I take 100mg before bed to help stay asleep through the night. My doc recommended taking it throughout the day as well to increase sleep. It does, but I have had heart palpitations since increasing, especially if I take more than 100mg in a single dose. So interesting how this supplement interacts with each individual. My body is quite sensitive to anything I take, which accounts for the pounding heart."

8 / 10
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51 Report
  • Nesst
  • Taken for less than 1 month
  • November 2, 2020

For Dietary Supplementation "I started taking l-theanine a month ago. At first it caused me to have horrible nightmares. I've never had heartburn before, but now I do. I've been in a super weird mood too. Not feeling like myself. I've also noticed random heart palpitations."

1 / 10
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39 Report
  • Ang
  • Taken for less than 1 month
  • October 24, 2020

For Dietary Supplementation "I tried just one pill last night and shortly after felt really relaxed, like that feeling when you’re about to fall asleep. Then my heart was beating closer to 125 bpm for at least an hour or more. I felt dizzy and also nauseous. I won’t be taking this again"

1 / 10
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39 Report
  • Jjrr
  • August 15, 2020

For Dietary Supplementation "My doctor suggested 100mg 2x daily for general anxiety. I was reluctant in taking my other prescribed anxiety meds (I.e, Xanax) so I figured I’d give this natural alternative a try. I took the Integrative Therapeutics brand because I’d had good experiences with their lavender oil pills (which do work for me by the way). I took my first pill of 100mg about 15 after breakfast. By the 45 minute mark, I was beginning to have the worst heart palpitations of my entire life. I thought I was going into convulsions. I tried to eat some bread to absorb the pill but it began to feel as though my mouth wouldn’t function. I felt like I was losing control of my body. I was beyond irritated and incoherent. Mind you, I’ve suffered from anxiety attacks for the past five years but nothing like this before. I’m also a 23 year old, healthy woman. I’m not on any other medications. The extremely high heart rate lasted for close to two hours. This may work for some but not me."

1 / 10
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39 Report
  • smitty
  • March 28, 2016

For Dietary Supplementation " I didn't know until I started reading the reviews how good this product really is i have add and I can tell you that it takes away the blues more specifically it gives you the power to finish your work"

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69 Report
  • karek...
  • Taken for less than 1 month
  • September 24, 2019

For Dietary Supplementation "I told my Psych that the clonazepam isn't working as well as it used to (and I'm going to be slowly tapering off the drug so I can be free of that prison!), and he recommend I use theanine (200 mg, 2 times per day, as needed). The first time I used it, within 30 minutes I was so relaxed - peaceful, calm, and it was easier to read an article because I wasn't always getting distracted. Taking 200 mgs in the morning and then again at night was great, and now that I've started tapering off my Clonazepam, I am using theanine to help with slight withdrawal symptoms. I'm praying this is what will finally get me off the benzo!! This stuff is fantastic...for me. Just be sure to talk with your doc on how to taper off any benzos before you do it yourself. Going cold turkey can be deadly. Only issue is that it seems to make me a little foggy for a short period of time during the morning. But my work product is MUCH better - especially when taking before drinking coffee."

9 / 10
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45 Report
  • Tony
  • October 27, 2019

For Dietary Supplementation "Took 200mg a day in the morning. Had a couple of stressful weeks and wanted to try theanine after some research on the web. Tried it for 2 days, then 2 days off. Then for 5 days straight then quit. First 2 days were okay, it reduced stress a lot. It did not increase that real focus but it did reduce distraction and other stimuli. The effect was pretty admirable for just an off- the-shelf supplement. Also deep sleep and pretty damn deep dreaming. During the 5 day period I pretty much got used and adjusted to the positive effects. Started to get bad headaches from it, my neck and jaw muscles got stiff as hell. Everything started to feel distant and off. It is way too easy to sort off "zone out" on this stuff. Would not recommend it. Non polarized reviews and mentions of side effects require some online digging to find."

2 / 10
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44 Report
  • GBano
  • Taken for less than 1 month
  • January 11, 2021

For Dietary Supplementation "Tried to take for general anxiety and for calmness. Just 100 mg 3 days in a row caused the opposite; insomnia, anxiety, and also a strange capability to bring up bad memories. Moved me more towards a depressive state of mind."

1 / 10
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34 Report
  • Wendy
  • Taken for less than 1 month
  • February 1, 2020

For Dietary Supplementation "Initially really benefited from the calm feelings when I took 200 mg at bedtime. Fell asleep more easily and had relief from falling asleep anxiety. After a few weeks, however, I started getting debilitating headaches, fogginess, dizziness, and fatigue. It confined me to home. I am very disappointed."

2 / 10
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41 Report
  • mesaa...
  • Taken for 2 to 5 years
  • January 20, 2017

For Dietary Supplementation "This works on my dog's anxiety, my anxiety and my college son's anxiety. We all get relief within 15 minutes of taking this. I actually found it orinally from my vet (expensive anti anxiety dog pill ingredients l theanine and meat flavoring). I keep buying tablets in the large foil bag on EBAY (the ones for humans not dogs!). It is better than an anti anxiety pill as there is no exhaustion or other side effects, just a calming feeling that allows you to relax a bit and think I buy a huge bag and that makes it cheap. The capsule form is more expensive"

10 / 10
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61 Report
  • Anonymous
  • Taken for less than 1 month
  • July 17, 2020

For Dietary Supplementation "I only took two pills (200mg each pill) over two days. The first day I seemed more focused, noticed I was reading through articles faster and seemed more alert, but not "wired." The second day, I felt really dizzy and brain foggy, anxiety spiked to where I felt like I couldn't even go outside, let alone go somewhere specifically, rapid heart beat, and frequent trips to the bathroom. Threw the bottle in the trash and hopefully things will level back out in the next couple days."

1 / 10
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37 Report
  • Bunpoh
  • Taken for less than 1 month
  • March 18, 2019

For Dietary Supplementation "After years of stress and trauma, became depressed and anxious with binge eating. Started Wellbutrin last April, and changed my job to better circumstances, stopped with further stress. Started having panic attacks, previous symptoms, additionally: fatigue, irritability, perimenopausal and low thyroid symptoms, rapid weight gain. Naturopath diagnosed adrenal fatigue, went off Wellbutrin (no issues), started L Theanine, 100 mg 2x a day, and a third before bed if I feel I need it, as well as Ashwagandha 2x a day. When stressed by events, I take 200 mg instead of 100mg, am overcome with a sense of calm and well being, like the first time I took it. Daily for over 2 weeks now, much better baseline anxiety level, wiped out my irritability, panic. That plus the Ashwagandha has given me my energy back and my sense of humor, ability to enjoy life, motivation. Binge eating us still a problem. Testing thyroid, hormone levels for further treatment."

8 / 10
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46 Report
  • Maz
  • September 2, 2020

For Dietary Supplementation "So I suffer from BPD & every type of anxiety I guess. I found L-theanine & bought 450mg ones. Took 2 pills before sleeping. Within 30 mins was knocked out without the daily suicidal thoughts. Everything was going SO well. HOWEVER..A month later..I was perfectly fine until I had a stomach ache. I went toilet a number of times & nothing was coming out. The following night. I had diarrhoea. THE WORST EVER experienced in my life!! It was 2:30am & my stomach did't let me sleep so I went to the toilet. Story short. ended up unconscious in the hallway. Once I gained conscious I ran to the toilet again for the other half of rapid fire..it took all my energy. Today, after 2 months, again, was laughing with mum until I had the worst stomach ache out of nowhere. I felt my body shutting down on me. I rushed to the toilet with the same signs & rapid fire before falling unconscious. Now I know it is L-Theanine I WILL NOT TRY THESE AGAIN. PLEASE DO NOT TRY THIS."

1 / 10
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35 Report
  • Lili
  • Taken for 1 to 6 months
  • December 30, 2020

For Dietary Supplementation "I've been using 200mg of l theanine combined with caffeine on and off for about 4 months now. At first, it was okay but I would have this weird dizziness that would fade away after some time. I loved the way it kind of made me 'wake up' for hours so I could work and study with full focus. However, this month and last month has been horrible for me with regards to taking these pills. I've started to feel tingly and numb in the hands and feet and I have this awful dizziness accompanied by a horrible heartburn. I feel like I am living in another dimension right now as everything around me is spinning. I took the pills last night for me to finally realise that this isn't for me. I did not sleep all night long! I still feel restless 10 hours later and the numbness, dizziness, and heartburn are still there. I am a perfectly healthy woman and trust me this supplement isn't for everyone so be careful."

1 / 10
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31 Report
  • Hallon
  • Taken for less than 1 month
  • September 14, 2019

For Dietary Supplementation "I was very stressed on the last weeks so I thought that it’s time to try this out. (I am eating healthy, working out every 2nd day) I took 100mg last night and slept very well. The next dose today morning then... mmm...I felt so strange...I couldn’t think clearly, I felt dizzy, I was at the store and suddenly I felt that I will loose my balance...I felt that my heart will explode. Personally I don’t recommend it."

1 / 10
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37 Report
  • PEP
  • December 30, 2016

For Dietary Supplementation "I had great results. It enhanced my cognitive thinking and lessoned my memory loss. The only problem was it gave me an unbelievable body odor. I could smell it but not sure if anyone else could. No one mentioned me smelling bad. I had to stop taking them because I couldn't stand the odor. My girlfriend takes it to help her blood pressure, which the doctors couldn't seem to regulate."

8 / 10
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52 Report
  • K Fen
  • June 21, 2017

For Dietary Supplementation "I already drank green tea, and did not realize this was in my other multivitamin supplement. This made me SO dizzy after a few days I could not drive or barely think straight. It also caused extreme fatigue for me. I am only 46 and in good health/fit. I world have crashed a car if I had driven in the last 24 hours. Please be careful with this."

1 / 10
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49 Report

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. This information is not intended to endorse any particular medication. While these reviews may be helpful, they are not a substitute for the expertise, knowledge, and judgement of healthcare professionals.

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