L-theanine and Headaches: What Users Say

• cla...
• Taken for 1 to 6 months
• May 14, 2021

For Dietary Supplementation "I am a 52-year-old average size (5'10', 180 lbs) 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 effects 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 lifesaver!"

• Fai...
• March 26, 2019

For Dietary Supplementation "I started L-Theanine taking 200 mg 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 doctor 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-Theanine, so I stopped it, after a few days, the pain went and my stomach healed up. I started it again, and after 3 days, the pains came back. To be absolutely sure, I stopped again and restarted after the pain stopped, same again, pain returned! Horrendous, bad vivid dreams as well, every night, and headaches by day."

• Sha...
• 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."

• Ton...
• October 27, 2019

For Dietary Supplementation "Took 200 mg 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 to 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 of 'zone out' on this stuff. Would not recommend it. Non-polarized reviews and mentions of side effects require some online digging to find."

• Wen...
• Taken for less than 1 month
• February 1, 2020

For Dietary Supplementation "Initially, I 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."

• Gen...
• Taken for less than 1 month
• July 11, 2019

For Dietary Supplementation "48-year-old male. Took it for general anxiety disorder, tried every med out there, almost everyone, some worked for a couple of years then stopped working so I go to another, on these meds for 19 years, very medication sensitive, got off all meds a year ago, still had a little anxiety so took l-theanine for about a week, worked really well for 7 days then suddenly developed a massive headache with extreme neck pain and dizziness. I stopped taking l-theanine 250 mgs. It's been 2 days since I stopped and the headache and neck pain are almost gone. Definitely not for me, allergic to pain lol!"

• kat...
• Taken for less than 1 month
• July 30, 2019

For Dietary Supplementation "I struggle with Generalized Anxiety Disorder, and I hate the way medicines make me feel! I saw some stuff about l-theanine and was excited to try something holistic with so many great reviews. At first, it was great; I noticed a calming effect within 30 minutes, I felt focused and alert, and overall in a good mood. I started taking 2 100 mg pills a day. After 2-3 weeks, I started noticing some changes. I felt like I just couldn’t focus at all, was in a weird depressed mood, wanted to sleep all the time, had no motivation to go workout. And if I didn’t take it at all, I felt HORRIBLE: dizzy, anxious, bad headaches. I stopped taking it about 3 days ago, and I’m trying to adjust. It just didn’t agree with me; maybe I should have just been taking it a few times a week rather than every day, but I think for now I’ll just steer clear."

• Alm...
• Taken for less than 1 month
• December 14, 2021

For Dietary Supplementation "Started taking a nightly dose of two 200 mg L-Theanine 'Theanine Serene' doses (recommended serving size) to 'support relaxation & focused attention' during the day. Slept okay, 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 the few that posts user experiences without diminishing or glossing over negative side effects. After 4 days, I am throwing the rest away, bottle to recycling, and recommend anyone use this amino acid with prior research & caution. I am a 61-year-old female in good health, take minimal supplements & no prescriptions."

• NYg...
• Taken for less than 1 month
• August 26, 2018

For Dietary Supplementation "The first time I took 100 mg of L-Theanine, it made me feel spacey, tired, and gave me a headache. It did calm me down, I felt my dopamine level rise, but the overall feeling was somewhat uncomfortable. A lot of sources recommend having 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 50 mg of L-Theanine to calm down, but it didn’t feel the same the second 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."

• RJA...
• 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 effect on my mental state - feeling relaxed, calm, as well as alert with mental clarity. This led me to buy L-theanine supplements, and unfortunately, dosages from 40 mg to 400 mg 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."

• Mic...
• Taken for less than 1 month
• June 30, 2022

For Dietary Supplementation "After reading the reviews, I ordered a bottle of 200 mg l-theanine capsules for anxiety, and I just took one early this morning. I didn't read anything about it needing time to take effect, 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 ibuprofen 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."

• Iss...
• Taken for less than 1 month
• October 10, 2021

For Dietary Supplementation "I've had sleep issues for the past week since stopping smoking cannabis. I took nutritional advice at a health food shop and bought L-theanine and Serotonin 5-HTP. I took one each of the capsules shortly before going to bed last night, following the directions on the bottles. I had a terrible night with stomach pains and nausea, and then a headache developed. These symptoms have remained more or less constant, with a slight reduction for a time after taking paracetamol. It is now 4:25 PM. I will not be taking either of these supplements again."

• jiv...
• Taken for 2 to 5 years
• April 27, 2021

For Dietary Supplementation "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 too 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've been using it to help sleep. Just 100 mg a few hours before bed helps, but doesn't keep me asleep for more than 4 hours. I find adding anything to this, like melatonin 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."

• lau...
• 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."