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User Reviews for L-theanine

Condition Avg. Rating Reviews Compare
Dietary Supplementation 5.4
93 reviews 628 medications

Reviews may be moderated or edited before publication to correct grammar and spelling or to remove inappropriate language and content. Reviews that appear to be created by parties with a vested interest in the medication will not be published. As reviews and ratings are subjective and self-reported, this information should not be used as the basis for any statistical analysis or scientific studies.

Reviews for L-theanine

Paola · Taken for less than 1 month January 16, 2021

For Dietary Supplementation: “Well I tried l-theanine because I was taking ashwaghanda but I was still getting a little of anxiety. The first day I started I felt tingly and a little weak but I thought maybe because it’s the first time so I kept on taking it. By the third time I started feeling a little sad for no reason and then the fourth day I didn’t feel like that but then the 5 Th day I felt negative again and I wasn’t feeling like this with ashwaghanda at all so yeah it’s not for everybody so be careful”

1 / 10
GB · 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
laughfactory · Taken for less than 1 month January 5, 2021

For Dietary Supplementation: “Took 100 mg of l-theanine and got a headache about two hours later, along with some brain fuzziness. Not entirely miserable, but definitely not desirable. Not sure if I've felt noticeably calmer or more focused.”

3 / 10
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
peaches · Taken for less than 1 month November 12, 2020

For Dietary Supplementation: “I and panic attacks for a few years now. I am on effexor (75 mg) and klonopin (very little.) Since my dr wants me off the klonopin and my anxiety has seemed to get worse I decided to find other alternatives. I looked to magnesium which really seems to help, I noticed L-theanine and like most of you I took it and felt the anxiety. I was like, what? Isn't it supposed to relax me? Well, I felt just the opposite. It subsided on its own and I wasn't sure it was the pill so I took it again at bedtime and yep, the same. So I won't be taking any more.”

1 / 10
Mild November 11, 2020

For Dietary Supplementation: “I took l-theanine at 200 mg dose at 2 am in combination with 100mg caffeine. I was hospitalized hours later. After the extreme weakness and dangerously low blood pressure it caused, Panic attacks almost drove me crazy. It doesn't seem to work well for everyone.”

1 / 10
Ma · Taken for less than 1 month November 7, 2020

For Dietary Supplementation: “After two days from taking 200 mg once a day. I felt dizziness and my body relaxed over”

2 / 10
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
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
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
Anonymous October 6, 2020

For Dietary Supplementation: “I have taken l-Theanine for several months after WLS. I suffer from anxiety and it has helped me a lot I drink it with coffee and it gets me through the day I take 100-200mg a day. Today I took 300mg I completed all of my College Assignments which I sometimes procrastinate on... I feel relaxed and motivated. I think it works for some of us but not for all. I love it!”

10 / 10
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
Maz September 2, 2020

For Dietary Supplementation: “Hi, 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 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
Anonymous · Taken for 1 to 2 years August 25, 2020

For Dietary Supplementation: “I get migraine with aura and numb limbs. I took 400mg and migraine disappeared slowly and not as bad as it gets. It was getting better before the ER IV benadryl and oxygen.”

10 / 10
BazinNZ · Taken for less than 1 month August 17, 2020

For Dietary Supplementation: “I read this supplement could help with withdrawals from Fluoxetine so took a 400mg dose (the only dosage I could find) with Magnesium before going to bed. I slept very poorly that night (could have been unrelated though). But the next day in the morning I experienced a feeling of panic and rapid heartbeat that completely freaked me out. I was driving and thought I was going to black out. I don't get panic attacks or severe anxiety so decided to stop this supplement immediately. I would recommend to start on a very low dose if you are going to try this.”

2 / 10
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
RJD · Taken for 2 to 5 years July 27, 2020

For Dietary Supplementation: “I've used the amino acid (not drug) L-theanine off and on for many years. I have inattentive type ADHD and generalized anxiety disorder (GAD). Depending on the dose, and what I take it with (coffee for example), it can make me feel simply a little bit calmer to being really sleepy, or in between. I have never had a problem with it, though for some reason it makes me hungry. ”

8 / 10
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
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
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
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
Betty April 22, 2020

For Dietary Supplementation: “I took this supplement this morning on the way to work. By the time I got to work I felt a little tired and dizzy. Within an hour, I became so nauseous and dizzy and my head felt tight and my neck got stiff and my arms started to feel weak and I got a little confused when trying to talk.. I had to leave and go home. I still feel all of those things. I will not be taking this supplement again.”

1 / 10
Rut · Taken for less than 1 month April 15, 2020

For Dietary Supplementation: “This drug increased heart rate, feel sedative and the same time more depressed and stressed.”

1 / 10
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
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

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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