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L-theanine User Reviews & Ratings (Page 4)

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

  • John
  • January 29, 2022

For Dietary Supplementation "Let’s be clear here, supplements like this have clearly helped some folks. I just happened to fall on the other side of things, and it needs to be shared. As with others I had a good first few days, and then day 4 and 5 were something entirely different, with heightened anxiety and depression deeper than I have felt before (worsened existing depression). I only took 200 mg in morning and 200 mg at night. Moral of the story is start low and start slow and write down what is happening. Talk to someone before taking this, because it can sincerely mess you up. I am a slow metabolizer and that may play a role in my experience, just not sure."

1 / 10
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14 Report
  • Tracey
  • Taken for less than 1 month
  • March 1, 2018

For Dietary Supplementation "I had been taking 3mg melatonin for sleep, but wanted to cut back as it left me feeling somewhat drugged. I found a product that contains 1.5mg melatonin plus 100mg l-theanine in a chewable, gummy form. It’s been working great for me for about a week. I feel this combo “lets” me sleep vs. “puts” me to sleep. However, I’m not sure sure if it’s the level of melatonin, the l-theanine, or the combo that works so well for me, but I’ll continue with it for awhile."

8 / 10
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28 Report
  • Almost...
  • Taken for less than 1 month
  • December 14, 2021

For Dietary Supplementation "Started taking nightly dose of two 200mg L-Theanine 'Theanine Serene' doses (recommended serving size) to "support relaxation & focused attention" during the day. Slept ok, but had VERY vivid, weird dreams each night to the point it made me distressed. Had a low grade headache this morning as well as slight stomach pain. Researched for negative side effects and bingo, here I am. This site is one of few that posts user experiences without diminishing or glossing over negative side effects. After 4 days am throwing the rest away, bottle to recycling, and recommend anyone use this amino acid with prior research & caution. I am a 61yr female in good health, take minimal supplements & no prescriptions."

1 / 10
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14 Report
  • Jenni...
  • Taken for 1 to 6 months
  • September 5, 2019

"I also struggle with generalized anxiety disorder. It doesn’t usually disrupt my life in such a forceful way luckily but it does cause me issues with falling asleep and focusing at work. I tried taking 200mgs at night and 100mg in the morning as suggested by several websites. I did this for almost two months and I started feeling VERY depressed and had some really dark thoughts. While this does happen occasionally it’s really usually only anxiety I struggle with. I decided to stop taking it to see what would happen, how could a supplement make me feel this way? Well within a few days this depression borderline crippling dark feeling I has totally disappeared. Took a month and tried again; smaller dose and tried a tea that also had it and experienced the same thing. Super strange...I think it’s worth a try but monitor your moods."

2 / 10
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22 Report
  • Jimmy
  • Taken for 1 to 6 months
  • September 14, 2018

For Dietary Supplementation "Every time I use this supplement I have either an intense dream or a full-blown graphic, bloody NIGHTMARE. Night before last it was about a bloody body being dragged around and hidden in my house! This is a known side effect of this supplement. The other potential benefits, of lowering cortisol and helping me stay asleep are all great. However, if I feel gross all day remembering the feelings of these dreams, that's not helping me be less stressed or focused in the day."

4 / 10
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25 Report

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  • NYgirl
  • Taken for less than 1 month
  • August 26, 2018

For Dietary Supplementation "The first time I took 100mg of L-Theanine it made me feel spacy, tired and gave me a headache. It did calm me down, I felt my dopamine level rise, but overall feeling was somewhat uncomfortable. A lot of sources recommend to have coffee with it. I loved the combination. It made me feel happy, motivated and energetic, but that didn’t last long. In 5 hours I started to have a bad crash. I had jitters all over my body and my heart rate was very high. I took 50mg of L-Theanine to calm down but it didn’t feel the same the 2nd time, not the same mood and I felt cranky, but it relaxed me. Since I don’t feel right after a calm down, I take 5-HTP after. I also pair L-Theanine with 5-HTP for sleep and have happy dreams, sleep and wake up with a smile. I recommend that combination for people who suffer from depression. For those who suffer from anxiety, don’t have it with coffee and be careful with it, calm downs can be pleasant. Could be the brand too, get a quality brand."

7 / 10
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25 Report
  • Nathan
  • Taken for less than 1 month
  • August 13, 2018

For Dietary Supplementation "Took this as I was suffering from Anxiety and wanted to avoid prescription medication. I took this before bed, felt little relaxed and slept well for 3 hours. Woke up after that and could never sleep after. Don't think this is right for me, so gave up"

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24 Report
  • Laura
  • Taken for less than 1 month
  • April 14, 2018

For Dietary Supplementation "After four days taking L Theanine - drinking Matcha Tea lattes 1-2 a day- I had a seizure. I noticed I felt kind of unusual after drinking the Matcha tea, calm but also kind of amped up at the same time. I didn’t sleep well, and after a night where I hardly slept (had a matcha latte at 5pm). The next morning I had a series of absence seizures. I am fairly sure it was from the L theanine because I have since researched it, and learned that it decreases the threshold for certain types of seizures, and increases the threshold for other types. I should have discontinued it when I noticed it’s effect on my sleep and nervous system."

1 / 10
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24 Report
  • 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
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16 Report
  • ONeil
  • April 25, 2023

For Dietary Supplementation "I have been trying for months to find a solution for my ADHD/anxiety. My therapist recommended exercise, meditation, journaling, and eating healthy (an existing habit). After months of no improvements, we were thinking to try rx medications, which is a fear of mine because of the side effects. Before seeing a psychiatrist, I did my own research and discovered L Theanine from a YouTuber’s video that sparked my interest. I went out the next day and bought L-theanine along with a few other supplements that were recommended, and I must say, the next day I felt completely fine, with no crippling anxiety, no overthinking, and I was more outgoing. I’m looking forward to more days like this. I hope L-theanine can help you as well!"

9 / 10
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6 Report
  • Egg...
  • Taken for less than 1 month
  • October 2, 2018

For Dietary Supplementation "I began taking this about 3 weeks ago as it had a lot of good reviews and seemed to be helpful for those with anxiety and social anxiety, which I have both of quite badly. I take 200mg daily, a few times I have doubled it and only one day did I feel slightly less anxious and by slightly less I mean barely any difference. I have not had any good results, it's like I'm not taking anything unless it's too soon to tell."

2 / 10
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19 Report
  • That...
  • Taken for less than 1 month
  • April 26, 2021

For Dietary Supplementation "I tried supplementing with L-Theanine for stress and noticed that I was getting random heart palpitations. When I stopped supplementing they went away. It also hides in a lot of supplements. A friends husband had the same issue from a natural sleep product that had L-Theanine in it."

1 / 10
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12 Report
  • Miche...
  • Taken for less than 1 month
  • June 30, 2022

For Dietary Supplementation "After reading the reviews I ordered a bottle of 200 mgs (l-theanine capsules for anxiety and I just took one early this morning. I didn't read anything about it needing time to take affect but it's been about 5 hours now and I don't feel less anxiety at all. I also don't feel productive or clarity of mind, I feel my usual burnout and chaotic mind. I just have this weird feeling in my head like the beginning of what might later be a headache so I took some ibuprofin to avoid that. I took this capsule specifically today because I'm having irritability and a hard time functioning and getting things done. I guess if you didn't have a bunch of demanding and inconsolable children you're caring for then this may feel like it works. Has anyone tested this with kids screaming and yelling in the background and constantly asking for things and being dissatisfied? I doubt it. I'm also having back pain from tensing up but that might just be my anxiety."

1 / 10
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8 Report
  • RJAYX
  • Taken for 1 to 6 months
  • February 2, 2022

For Dietary Supplementation "MICRO DOSAGES Hi - I posted last year explaining how well I felt after drinking green tea - however 40mg-200mg of the supplement made me feel very uncomfortable (mentally and physically). I also mentioned giving micro dosing a go. I have been taking tiny amounts of the supplement in powder form at night and in the morning for a 2 months and it has done me wonders."

10 / 10
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9 Report
  • Oliver
  • Taken for 1 to 6 months
  • May 24, 2022

For Dietary Supplementation "I appreciate this does work for some people and I agree it does relax you...until it wears off! For me it gave me heart flutters and the worst anxiety ever once it wore off. I just didn't feel myself and felt like I had a very low mood. Would not recommend but I appreciate everybody's body chemistry is different. I'll stick to meditation and herbal teas."

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8 Report
  • Lynne
  • Taken for 1 to 6 months
  • August 22, 2023

For Dietary Supplementation "I can't remember if I posted about this before so apologies. I've been taking 350mg once a day. I split the second 200mg powdered capsule in half. I'm trying to self-wean off my benzos as I've developed resistance and they're not effective anymore. Do not mix the two! I feel calmer and more sedated. I do get quite groggy, but I'm calm and everything just melts away without any side effects. I can handle things better. The only thing I'm worried about is my racing heart, developing resistance to it, and the vivid dreams. I'll give it more time to see if my anxiety (like racing thoughts, panic attacks and thoughtless rambling) and PMDD symptoms continue to improve. Last cycle was milder and it surprised me. I refuse to go on hormones or try another SSRI. I threw that trash Paxil in the garbage. L-Theanine seems to be working out. My cortisol hormone levels were high and I just got my blood tested last week. I was told they lowered. I'm so happy to hear that."

8 / 10
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4 Report
  • Terak...
  • Taken for 1 to 6 months
  • December 12, 2023

For Dietary Supplementation "I have been taking l-theanine for almost a year now with stops, of course. The longest I have taken it was about 2-3 months, every day 400mg in the morning and 200mg at lunch (if needed). I started at a lower dose but moved up quickly. It has helped me a lot. I have C-PTSD, generalized anxiety, ADHD, autism spectrum, and depression. I also suffer from PMDD. It doesn't work for every panic-anxiety-PTSD episode I get, but sometimes even diazepam doesn't help. Most of those episodes get better in half an hour; I regain the ability to think clearly again, though I still experience intense emotions. However, they stop controlling me. It doesn't help me with sleep though; I actually get quite active. I can honestly say that l-theanine is saving me from addiction to benzodiazepines. Now I only take diazepam about 2 out of 10 times I have breakdowns. It doesn't give me brain fog; it actually lowers my heart rate (I have 90BPM almost constantly). The only issue I have with it is that it only works for 4 hours."

10 / 10
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3 Report
  • Guy
  • Taken for 1 to 2 years
  • November 5, 2022

For Dietary Supplementation "Most effective supplement I have ever tried. Sublingual dose works in minutes. The anxiety just kind of melts away. Works great with panic disorder and OCD. I take a half dose twice a day, but see what works for you. 10 out of 10"

10 / 10
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6 Report
  • Shel
  • Taken for less than 1 month
  • January 12, 2022

For Dietary Supplementation "I took 200 mg about a month ago for a few days to help with anxiety. It seemed to work at first, but then I felt more anxious as it wore off later. I also had a burning feeling in my stomach and reflux. The second day I took it with caffeine/coffee. I was very focused-like a robot, getting things done. The burning continued, even after taking my reflux meds. I again, felt anxious when it wore off. Recently I got just took some melatonin and didn’t realize it had 200 mg of l-Theanine. I later had cramping and diarrhea. That is not normal at all for me. I also woke up in the night feeling very anxious. I think it’s all from the L-theanine. I would not have taken recently if I’d known it was in the melatonin. Magnesium works much better for me for calm and sleep, but you have to use the glycinate kind or it can cause gastro issues. I think it could help some people, but the side effects were terrible for me. In fact, it caused anxiety instead of helped it."

3 / 10
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8 Report
  • Stoic...
  • Taken for less than 1 month
  • March 8, 2023

For Dietary Supplementation "Decided to try this to help with minor anxiety - not interested in taking prescriptions. Started with 400mg/day (200 mornings, 200 evenings), felt good, and was generally stress-free for a few days but wanted to see how I'd do with 300/300mg a day (600mg total for a day). I'm 6'4", 200 lbs. Found myself having a strange reaction one night with very low blood pressure and could literally feel my breathing getting way too shallow. I already have low blood pressure. Backed off of this and only did 200mg in the morning, cut way back on caffeine, and feel much better. Just be careful if you go above 400mg/day. Also, the half-life of l-theanine is very long and stays in your system for a while so keep this in mind. Overall I do recommend l-theanine if you know what you're doing."

9 / 10
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5 Report
  • Anonymous
  • August 6, 2021

For Dietary Supplementation "100 to 200 mg 3 x a day helps me with generalized anxiety disorder. I also have powdered form. 1/8 tsp under tongue relaxes my brain. Lowers cortisol at night for better sleep. Tapering off gabapentine with ltheanine and melatonin before bed. God bless, keep looking forward.."

9 / 10
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9 Report
  • Amway...
  • Taken for less than 1 month
  • February 25, 2023

"I am grateful to have come across this website review page. It occurred to me, after experiencing lightheadedness, near-fainting spells, and heart palpitations for the past week and a half, that it could be related to something I was taking. I decided to search for information on L-Theanine, as I had added 50 mg of it to my nightly routine about 3.5 weeks ago to aid in sleeping, which it did. I recently visited the doctor to have an EKG and bloodwork done to investigate these new symptoms, but everything came back normal. However, I did notice a drop in my blood pressure from its usual 120/80 to 90/70, and my heart rate decreased from the 80s to the 70s. Upon reading the reviews, it appears that my recent issues could be linked to L-Theanine. I appreciate everyone sharing their experiences, as everyone is affected differently by various substances. Although some may benefit, others may not. I am currently grateful and have decided not to take L-Theanine tonight."

5 / 10
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5 Report
  • RJAYX
  • Taken for less than 1 month
  • October 26, 2021

For Dietary Supplementation "I discovered L Theanine by accident through drinking green tea which I noticed had a hugely positive affect on my mental state - feeling relaxed calm as well as alert with mental clarity. This lead me onto buying L Theanine supplements and unfortunately dosages from 40mg-400mg each caused me physical and mental discomfort - headache, nausea, anxiety and lack of focus. I wondered if I am sensitive to the L Theanine and should try out micro dosages."

1 / 10
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8 Report
  • Lone...
  • Taken for less than 1 month
  • September 6, 2021

For Dietary Supplementation "I took one 200MG pill of l-theanine to help me get rid of anxiety about one hour before I wanted to get to sleep. It elevated my anxiety with horrifying nightmares. In these nightmares people looked like hideous mutants. I woke up several times, or I think that I did, and the horror was still playing. The nightmare came to life. That was an experience that I never want to relive! Ashwagandha works far better for me."

1 / 10
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  • joe
  • Taken for 1 to 6 months
  • January 24, 2021

For Dietary Supplementation "I've tried using L-Theanine 2 separate times (about a week each time) to help fall and stay asleep. Although it was effective in calming you down, I felt it made my mind too alert to fall asleep, and when I did, I'd only get very light Stage 1 sleep for a couple hours, then be up for a while around 2:00 a.m. I would recommend for daytime use but not for sleep."

2 / 10
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9 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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