L-Theanine 1000 mg, 60 Vegan Capsules

L-theanine is the calming amino acid in green tea, and it works at 200 to 400 mg by raising alpha brain wave activity within 30 to 45 minutes of oral intake. Remedy's Nutrition L-Theanine delivers 1000 mg per vegan capsule with no fillers, lab-tested for purity in a cGMP facility in the USA.
This page covers what L-theanine actually does in the brain, the 8 evidence-backed benefits, how to dose for stress, sleep, and focus, the caffeine stack ratio that works, drug interactions across 10 classes, and who should not take it.

L-theanine promotes calm focus at 200 to 400 mg without drowsiness, with peak effect in 30 to 45 minutes. Each capsule holds 1000 mg, 5 times the most-studied 200 mg dose, so talk to a clinician before use. Pair with caffeine in a 2:1 ratio for focus, or take 30 to 60 minutes before bed for sleep.

Key Takeaways

L-theanine works at 200 to 400 mg in 30 to 45 minutes.
Calm focus comes from alpha brain wave activation, not sedation.
Caffeine stack ratio is 2:1 L-theanine to caffeine.
Safe for 4 to 8 weeks of daily use at 200 to 400 mg.
Drug interactions span 5 classes including BP and SSRIs.
Avoid in pregnancy and BP under 90/60 mmHg.
Remedy's offers 1000 mg vegan capsules with no fillers.

What Is L-Theanine?
L-theanine is a non-protein amino acid found almost exclusively in the leaves of Camellia sinensis (the tea plant) and in trace amounts in the Boletus badius mushroom. Its content varies widely with harvest season, cultivar, and growing method, and shade-grown teas such as gyokuro and matcha are particularly rich in it.[1]Theanine Variability in Matcha, Sencha and Gyokuro — PubMed View source

Studied range: 100 to 900 mg/day, with 200 mg the most-tested single dose.

Unlike most amino acids, L-theanine does not build muscle or repair tissue. Its sole pharmacological role is in the central nervous system, where it modulates GABA, dopamine, and serotonin pathways while raising alpha brain wave activity. This is why a cup of green tea calms you down even though it contains caffeine. For a full breakdown of the science, see our complete L-theanine guide.
Why Remedy's Nutrition L-Theanine
Remedy's Nutrition L-Theanine 1000 mg sets the bar on three measurable specs: dose per capsule, purity, and capsule format. Most retail L-theanine products deliver 100 to 200 mg per capsule with fillers; ours delivers 1000 mg per vegan capsule. That is above the 100 to 400 mg doses most trials used, so discuss it with a clinician before use.

What You Get
Why It Matters

1000 mg L-theanine per vegan capsule
5x the most-studied 200 mg dose and above the 900 mg/day trial maximum; use with clinician guidance.

Zero fillers, binders, or dyes
No magnesium stearate, no titanium dioxide, no artificial colors. Just pure L-theanine and a vegan HPMC capsule.

Made in USA, cGMP-certified facility
FDA-registered facility with batch-level quality control and lab verification of every production run.

Lab-tested for purity
Third-party testing confirms L-theanine content matches label claim and product is free of heavy metals.

60 vegan capsules per bottle
A 60-day supply at 1 capsule per day. Suitable for vegan, vegetarian, gluten-free, and non-GMO diets.

Non-habit forming
No documented tolerance or dependence across published trials up to 8 weeks of daily use.

The Top 8 Evidence-Backed Benefits of L-Theanine
L-theanine has been tested in dozens of mostly small, short human trials, nearly all at 100 to 400 mg per dose. A 2026 meta-analysis of 31 RCTs found a robust short-term attention benefit, while stress effects were modest and anxiety effects inconsistent.[2]L-Theanine Meta-Analysis of 31 Randomized Trials — PubMed View source

Benefit
Key Clinical Finding
Effective Dose

Acute stress reduction
Reduced heart-rate and s-IgA stress responses in a 12-person crossover trial; pooled effect rated modest[3]L-Theanine Reduces Stress Responses — PubMed View source

200 mg, 30 to 45 min pre-stressor

Sleep quality
Improved some sleep-quality measures in a few small trials, without sedation
200 to 400 mg, 30 to 60 min pre-bed

Calm focus with caffeine
Small-to-moderate gains in attention switching and reaction time in a 2025 meta-analysis
200 mg L-theanine + 100 mg caffeine

Anxiety adjunct
Did not beat placebo for anxiety in an 8-week GAD add-on trial; sleep satisfaction improved (Sarris 2019)
450 to 900 mg/day

ADHD-related sleep
Improved actigraphy sleep efficiency, not attention, in a pediatric ADHD trial (Lyon 2011, boys 8 to 12)
400 mg/day for 6 weeks

Alpha brain wave activation
Alpha-band EEG changes in small studies; direction varies by task
200 mg single dose

Blood pressure modulation
Small studies suggest blunted stress-related rises; no reliable mmHg figure
200 mg pre-stressor

Mental clarity in MCI
A green tea extract plus L-theanine blend, not pure L-theanine, improved some memory and attention measures in 91 adults with MCI (Park 2011)
1,680 mg/day of the blend, 16 weeks

How L-Theanine Works in the Brain
L-theanine produces calm focus through 4 documented mechanisms that act simultaneously: alpha brain wave activation, GABA modulation, glutamate receptor modulation, and dopamine plus serotonin balancing. The combined effect is a relaxed but alert mental state, distinct from sedation or stimulation.[4]L-Theanine NMDA Glutamate Receptor Mechanism — PubMed View source

Mechanism
What It Does
Functional Effect

Alpha brain wave boost
Increases 8 to 13 Hz alpha-frequency EEG activity in occipital and parietal cortex within 30 to 45 min
Relaxed-alert state similar to meditation; reduced mental chatter

GABA receptor modulation
Animal studies report raised brain GABA levels; direct GABA-A binding is not established in humans
Calm without drowsiness; better sleep onset

Glutamate receptor modulation
Structural analog of glutamate with weak receptor binding; a 2017 cell study found partial co-agonist activity at NMDA receptors
Reduced stress reactivity; lower cortisol spike under load

Dopamine and serotonin balance
Modulates striatal dopamine and raises brain serotonin in animal studies
Mood support; complementary to caffeine's dopamine release

How Much L-Theanine Should You Take?
L-theanine dosage ranges from 100 mg to 900 mg per day in published trials, with most healthy adults responding to 200 to 400 mg. Start at the low end of the range for your use case and adjust upward over 1 to 2 weeks. One Remedy's capsule holds 1000 mg, above every dose in this table, so talk to a clinician before using it.

Use Case
Effective Dose
Timing
Duration

Acute stress (pre-event)
200 mg
30 to 45 min before stressor
Single dose as needed

Daily stress management
200 mg, 1 to 2x/day
Morning and/or midday
4 to 8 weeks then reassess

Sleep support
200 to 400 mg
30 to 60 min pre-bed
Nightly as needed

Caffeine stack (focus)
200 mg + 100 mg caffeine
With morning coffee
Daily as needed

Anxiety adjunct (with Rx)
450 to 900 mg/day (trial dose)
As directed by prescriber
8 weeks; no anxiety benefit over placebo

ADHD-related sleep (children)
400 mg/day
Split, breakfast and after school
6 weeks then reassess

Higher need / non-responders
400 to 600 mg
Split across day
Reassess after 4 weeks

For a step-by-step dosing protocol including how to find your minimum effective dose, see our L-theanine dosage guide.
1000 mg Capsule vs the Doses Studied
Most published L-theanine trials used 100 to 400 mg per dose, and the highest daily dose in the trials cited on this page was 900 mg. One Remedy's capsule holds 1000 mg, so a single capsule is 5 times the most-studied 200 mg dose and above that 900 mg/day maximum.

Studied Dose
Where It Was Used
One 1000 mg Capsule Is

100 mg
Caffeine pairing trials (with 50 mg caffeine)
10x this dose

200 mg
Most-studied single dose; 4-week stress trial
5x this dose

400 mg/day
Pediatric ADHD sleep trial; 28-day adult trial
2.5x this dose

450 to 900 mg/day
8-week GAD add-on trial (highest daily dose cited)
Above this range

Dividing capsule powder by eye is not a reliable way to measure 100 or 200 mg, and safety at 1000 mg/day has not been studied. Talk to a clinician before using doses above those studied, especially if you take blood pressure or CNS medications.

When to Take L-Theanine
Timing of L-theanine matters more than total daily dose because the 60 to 75 minute half-life means effects fade within 2 to 3 hours of a single dose. Match the dose timing to when you need the calm-focus window, not on a fixed schedule.

Time of Day
Purpose
Dose
Pair With

Morning (6 to 9 AM)
Calm-focus workday start
200 mg
Coffee or tea (100 to 150 mg caffeine)

Mid-morning (10 to 11 AM)
Deep focus block
100 to 200 mg
Optional second coffee

Pre-stressor (event-based)
Presentation, meeting, exam
200 mg, 30 to 45 min prior
Water only

Mid-afternoon (2 to 4 PM)
Avoid energy slump without caffeine
100 to 200 mg
Solo

Evening (6 to 8 PM)
Wind-down transition
200 mg
Herbal tea (no caffeine)

Pre-bed (30 to 60 min before)
Sleep onset support
200 to 400 mg
Magnesium glycinate optional

The L-theanine plus caffeine stack at a 2:1 ratio (200 mg L-theanine + 100 mg caffeine) is the most-tested combination in published cognitive trials. In a 27-person trial, 100 mg L-theanine plus 50 mg caffeine improved attention-switching speed and accuracy at 60 minutes.[5]L-Theanine Plus Caffeine Attention Switching — PubMed View source

2:1 ratio: 200 mg L-theanine with 100 mg caffeine — the standard tested pairing.

Cut-off: stop caffeine 8 hours before bed; L-theanine alone is fine after that.

The mechanism is complementary: caffeine blocks adenosine receptors (alertness), while L-theanine raises alpha brain waves (calm focus). The result is the focused alertness that experienced tea drinkers have valued for centuries, replicated in modern coffee plus L-theanine routines. For the complete stacking protocol including ratios and what to avoid, see our L-theanine and caffeine guide.
L-Theanine for Anxiety and Stress
L-theanine for anxiety is best used at 200 mg taken 30 to 45 minutes before a known stressor, An 8-week add-on trial in generalized anxiety disorder used 450 to 900 mg/day and did not beat placebo for anxiety. Small trials suggest it can blunt physical stress responses without sedation.[6]L-Theanine Adjunctive Treatment of Generalized Anxiety Disorder — PubMed View source

Situation
Dose
Timing
What to Expect

Presentation, exam, interview
200 mg
30 to 45 min before
Slower heart-rate climb, steadier delivery, no dulling

Daily background stress
200 mg, 1 to 2x
Morning and midday
Fewer stress spikes across the workday

GAD adjunct (prescriber-led)
450 to 900 mg/day (trial dose)
As directed by prescriber
No anxiety benefit over placebo in an 8-week trial

Panic-type surges
Not first-line
—
Seek clinical care; L-theanine is not a rescue medication

Evidence here is modest: a 2020 systematic review of 9 RCTs concluded 200 to 400 mg/day may help reduce stress and anxiety under stressful conditions, while calling for larger, longer trials.[7]Green Tea Amino Acid L-Theanine and the Ability to Manage Stress and Anxiety: Systematic Review — PubMed View source For dose-by-symptom detail, see our guide to l-theanine dosing for anxiety.
L-Theanine for Sleep
L-theanine for sleep works at 200 to 400 mg taken 30 to 60 minutes before bed, with improvements in some sleep-quality measures in a few small randomized trials. Unlike melatonin (which shifts circadian timing) or GABA agonists (which cause sedation), L-theanine works by reducing pre-sleep mental chatter and calming the stress response that keeps you awake.[8]L-Theanine Sleep Quality Pediatric RCT — PubMed View source

Dose: 200 to 400 mg, 30 to 60 minutes before lights out.

Best for: a busy mind at bedtime rather than a shifted body clock.

Not for: circadian problems such as jet lag — that is melatonin territory.

This is why L-theanine is non-sedating: you do not feel drugged or groggy, and it does not lengthen sleep duration on its own. It improves sleep quality, not sleep amount. For dosing, timing, and what to stack it with, read our L-theanine for sleep guide.
L-Theanine for Focus and ADHD
L-theanine supports focus mainly through the caffeine pairing: 200 mg L-theanine with 100 mg caffeine improved attention switching and reduced distractibility across a systematic review of cognitive trials. For diagnosed ADHD the published evidence is 1 pediatric sleep trial, not a treatment claim.[9]Cognitive-Enhancing Outcomes of Caffeine and L-Theanine: Systematic Review — PubMed View source

Afternoon slump: 100 mg on its own, no added caffeine after 2 PM.

Pediatric ADHD data: 400 mg/day for 6 weeks improved actigraphy sleep in boys ages 8 to 12.

Students and shift workers use the same 2 doses differently: 200 mg with caffeine for the demanding block, then 100 mg alone later to stay calm without extending caffeine into the sleep window. Our l-theanine for ADHD and focus guide covers the prescriber-led protocol in full.
Green Tea vs L-Theanine Capsules
L-theanine in a brewed cup of tea varies widely with tea type and brewing, so reaching the 200 mg research dose from tea means several cups and their caffeine. Capsules separate the calm from the stimulant.[10]Acute Effects of Tea Constituents L-Theanine, Caffeine and EGCG on Cognition — PubMed View source

Source
L-Theanine
Caffeine
Note

Green tea, 8 oz cup
Variable
Yes
Several cups for 200 mg, plus their caffeine

Matcha, 1 tsp
High for a tea (shade-grown)
Yes
Quality ranges widely between products

Black tea, 8 oz cup
Variable
Yes
Brands rarely publish theanine figures

1000 mg capsule
0 mg
5x the 200 mg research dose; caffeine-free

Tea stays the better ritual and the better antioxidant source. Capsules win when you need a caffeine-free option or are within 6 hours of bedtime.
L-Theanine vs Ashwagandha, GABA, and Melatonin
L-theanine, ashwagandha, GABA, and melatonin are 4 popular calming supplements with fundamentally different mechanisms and use cases. Picking the right one depends on your goal: acute calm-focus, chronic stress, sleep onset, or circadian reset.

Supplement
Best For
Mechanism

L-Theanine
Acute calm focus, pre-stressor, sleep quality
30 to 45 min
Alpha brain waves, GABA modulation

Ashwagandha
Chronic stress, cortisol reduction, daily resilience
2 to 4 weeks
HPA axis modulation, adaptogen

GABA
Direct GABA receptor stimulation (BBB crossing controversial)
30 to 60 min if effective
GABA-A agonism (peripheral)

Melatonin
Jet lag, shift work, circadian reset
30 to 60 min
MT1 and MT2 receptor agonism

For the full 4-way decision tree and which to stack with what, see our L-theanine vs ashwagandha, GABA, and melatonin comparison.
What to Stack L-Theanine With
L-theanine layers cleanly with 4 common supplements because none of them share its alpha-wave mechanism. Magnesium is the most-searched pairing: 200 mg L-theanine with magnesium glycinate in the evening targets mental chatter and muscle tension at the same time.

Pairing
Why It Works
Typical Timing

Magnesium glycinate
Mineral cofactor for muscle and nerve relaxation; no mechanistic overlap with L-theanine
200 to 400 mg each, 30 to 60 min pre-bed

GABA
A GABA plus L-theanine mixture shortened sleep latency in a rodent study; human data are lacking
Evening only

Ashwagandha
Multi-week HPA-axis adaptation covers the chronic stress side L-theanine does not
Ashwagandha daily, L-theanine as needed

Caffeine
2:1 ratio (200 mg + 100 mg) is the most-tested cognitive combination
Morning and early afternoon

Melatonin
Fixes circadian timing while L-theanine handles pre-sleep mental chatter
1 to 3 mg melatonin, 60 min pre-bed

Add 1 supplement at a time over 1 to 2 weeks. Stacking 3 new products the same night makes it impossible to tell which one worked, and which one caused the grogginess.[11]GABA and L-Theanine Mixture Decreases Sleep Latency — PubMed View source
Side Effects and Drug Interactions
L-theanine side effects are uncommon and mild in trials, with headache, mild nausea, and lowered blood pressure being the 3 most reported. A 28-day trial at 400 mg/day in 30 healthy adults found no clinically relevant safety changes.[12]L-Theanine 28-Day Safety Trial — PubMed View source Drug interactions span 10 medication classes worth discussing with a prescriber.

Drug Class
Interaction Mechanism
What to Do

Blood pressure medications
Possible additive BP-lowering; size of effect not established
Monitor BP; lower dose if symptomatic hypotension

Stimulants (Adderall, Vyvanse)
May blunt prescribed stimulant focus boost
Discuss with prescriber before stacking

Sedatives, benzodiazepines
Additive central calming via GABA modulation
Avoid combining without doctor guidance

Antidepressants (SSRIs)
Theoretical serotonin modulation
Discuss before adding; monitor mood

Chemotherapy agents
Animal data shows altered drug levels for some agents
Do not use during chemo without oncologist clearance

Alcohol
Additive sedation in higher doses; potentiates calming
Avoid combining; especially driving

Levodopa (Parkinson's)
Theoretical dopamine modulation
Discuss with neurologist

Anticoagulants
No clear interaction documented
Generally safe; monitor INR if concerned

Anticonvulsants
Theoretical glutamate modulation
Discuss with neurologist before use

MAOIs
Theoretical serotonin and dopamine interaction
Avoid without psychiatric supervision

For the full safety review including red-flag symptoms that warrant stopping, see our L-theanine side effects and drug interactions guide.
Who Should Not Take L-Theanine
L-theanine is well-tolerated by healthy adults, but 5 groups should avoid it or use only with medical supervision. The most important contraindication is pregnancy, where safety data does not exist.

Group
Reason
Action

Pregnancy and breastfeeding
No human safety data in pregnancy or breastfeeding
Avoid; discuss with OB before use

Children under 8
Pediatric safety data limited to one ADHD trial in boys 8 to 12 (Lyon 2011)
Only with pediatrician supervision for specific indications

Low blood pressure (under 90/60)
May add to blood pressure lowering and worsen hypotension
Avoid or use very low dose with monitoring

Schizophrenia (without psychiatric care)
Used as adjunct in trials only under psychiatric supervision
Do not self-supplement; requires prescriber

People on multiple CNS medications
Additive sedation, BP, or mood effects possible
Discuss full medication list with doctor

What's in the Bottle
Remedy's Nutrition L-Theanine comes in a 60-capsule bottle with a single, simple formula: 1000 mg of pure L-theanine per vegan capsule. No fillers, no binders, no artificial colors, no titanium dioxide, no magnesium stearate. The capsule itself is plant-based HPMC (hydroxypropyl methylcellulose), suitable for vegan, vegetarian, and gluten-free diets.

Spec
Detail

Frequently Asked Questions

How much L-theanine should I take per day? +
Most trials used 100 to 400 mg per day, with 200 mg the most-studied single dose. The highest daily dose in the trials cited here is 900 mg. One capsule of this product holds 1000 mg, above those doses, so talk to a clinician before using it.

How fast does L-theanine work? +
L-theanine reaches peak blood levels in 30 to 50 minutes after oral intake, with alpha brain wave changes measurable within 30 to 45 minutes. The half-life is 60 to 75 minutes, so the calm-focus window is 1 to 3 hours per dose. No buildup is needed; first-dose effects are reliable.

Is L-theanine safe to take every day? +
Yes, daily L-theanine at 200 to 400 mg is safe for healthy adults based on 4-week and 8-week clinical trials. In 2007 the FDA raised no questions on a GRAS notice for L-theanine in foods at up to 250 mg per serving. No tolerance, dependence, or withdrawal has been documented in published trials lasting up to 8 weeks.

Does L-theanine make you sleepy? +
No, L-theanine is non-sedating at typical 200 to 400 mg doses. It promotes calm alertness via alpha brain waves rather than the drowsiness caused by GABA agonists or antihistamines. This is why it works as a daytime focus tool and also for sleep, where it lowers pre-sleep mental chatter without causing morning grogginess.

Can I take L-theanine with coffee? +
Yes. A 2:1 ratio (200 mg L-theanine + 100 mg caffeine) is a common pairing, and a 2025 meta-analysis found small-to-moderate gains in attention switching and reaction time in the first 2 hours. One 1000 mg capsule is far above the L-theanine amounts used in those trials.

What are the side effects of L-theanine? +
L-theanine side effects are uncommon and mild. The 3 most reported in trials are headache, mild nausea, and lowered blood pressure. A 28-day trial at 400 mg/day found no clinically relevant safety changes. Discontinue if blood pressure drops below 90/60 mmHg.

Does L-theanine interact with medications? +
Yes, L-theanine can interact with 5 medication classes: blood pressure medications (additive BP-lowering), stimulants like Adderall (may blunt focus boost), sedatives (additive calm), chemotherapy (animal data only), and SSRIs (theoretical serotonin modulation). Consult a prescriber before stacking with any prescription.

Is 1000 mg of L-theanine too much? +
1000 mg is more than any single dose in published trials, which mostly used 100 to 400 mg, and above the 900 mg/day highest daily dose cited here. Safety at 1000 mg/day has not been studied. Talk to a clinician before taking a full capsule, especially with blood pressure or CNS medications.

When should I take L-theanine for sleep? +
Take 200 to 400 mg of L-theanine 30 to 60 minutes before bed for sleep support. The 60 to 75 minute half-life means it covers the sleep-onset window without lingering into morning. Pair with sleep hygiene (cool room, no screens 60 min before bed) for best results.

Can children take L-theanine? +
Pediatric use should be supervised by a doctor. The single pediatric RCT (Lyon 2011) dosed 400 mg/day in boys aged 8 to 12 with ADHD for 6 weeks with no safety signals. Do not give to children under 8 without medical guidance.

Is L-theanine safe during pregnancy? +
No, L-theanine is not recommended during pregnancy or breastfeeding due to lack of human safety data across all 3 trimesters. The 2007 FDA GRAS notice covered L-theanine as a food ingredient, not supplement use in pregnancy. Discuss any supplement with your provider before use during pregnancy.

What makes Remedy's L-theanine different? +
Remedy's Nutrition L-Theanine delivers 1000 mg per vegan capsule with zero fillers, binders, or artificial colors. The product is made in the USA in a cGMP-certified facility and lab-tested for purity. Each bottle contains 60 capsules, a 60-day supply at 1 capsule per day. Suitable for vegan, vegetarian, and gluten-free diets.

Is 100 mg of L-theanine enough? +
For many adults, yes — 100 mg is a sensible 3 to 5 day starting dose, especially paired with 50 to 100 mg of caffeine. Most trials that show stress and attention effects used 200 mg, so move up if 100 mg feels flat. This product's 1000 mg capsule cannot be reliably divided into a 100 mg dose.

Can I take L-theanine with magnesium? +
Yes. A common evening pairing is 200 to 400 mg L-theanine 30 to 60 minutes before bed with 200 to 400 mg of magnesium glycinate. The 2 mechanisms do not overlap and no interaction is documented. Add one at a time over 1 to 2 weeks so you know which one is working.

How many capsules are in a bottle and how long does it last? +
Each bottle holds 60 vegan capsules of 1000 mg, a 60-day supply at 1 capsule per day. Each capsule is well above the 100 to 400 mg doses most trials used, so check with a clinician on how much to take.

You May Also Like

Magnesium Glycinate 1000 mg — evening mineral support that pairs with L-theanine for muscle tension and sleep onset

Ashwagandha 1000 mg — multi-week adaptogen for chronic stress, complementary to acute calm focus

GABA Calm 1000 mg — GABA-based evening blend studied alongside L-theanine for sleep latency

Melatonin 3 mg — circadian timing support when the issue is schedule rather than mental chatter