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GABAplex

Swanson
4.7
★ ★ ★ ★ ★
(191 ratings)
GABA 250 mg
Theanine 50 mg
Glycine 250 mg
Tyrosine 100 mg
Product Image
Score78
Useful GABA and low cost make this a practical calming blend. Secondary doses are light, and tyrosine weakens its sleep focus.
How scoring works
Quantity:60 Capsule(s) • (60 servings)
Goals:
Stress Relief
Sleep Support

Score 78

Useful GABA and low cost make this a practical calming blend. Secondary doses are light, and tyrosine weakens its sleep focus.
How scoring works
$16.19($0.26 per serving)
iHerb
$ 16.19
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Analysis

GABA at 250 mg reaches the start of a useful range, with 250 mg glycine adding a second inhibitory amino acid. Taurine, theanine, and tyrosine broaden neurotransmitter support.

Theanine at 50 mg and taurine at 100 mg are modest, while glycine is far below gram-level sleep use. Tyrosine can feel activating, making the blend more suitable for daytime balance than consistent bedtime use.

One capsule and low serving cost support convenience and value. BioPerine may alter absorption, but source and purity details for the amino acids are absent.

Who is it for
  • Adults seeking an inexpensive calming amino-acid blend
  • People wanting GABA with glycine
  • Users who prefer one capsule
Best for
  • Stress-relief routines
  • Daytime calm
  • General amino-acid relaxation support

Pros

  • Provides 250 mg GABA
  • Includes 250 mg glycine
  • Convenient one-capsule serving
  • Low serving cost

Cons

  • Theanine and taurine are modest
  • Glycine is below a sleep-focused dose
  • Tyrosine may be activating
  • Amino-acid purity details are absent

Warnings

  • GABA may cause drowsiness
  • BioPerine can alter absorption of some medicines
  • Tyrosine may interact with MAO inhibitors or thyroid medicines

Nutrient quality

81 Highest impact

The amino acids are clearly named, though premium-source and purity details are limited. GABA and glycine are useful blend amounts, while tyrosine, taurine, and theanine are modest.

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Ingredient transparency

81 Highest impact

Active amounts are stated and no proprietary blend hides a core dose. Missing excipient details and complete use directions leave the supplied label information incomplete.

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Customer satisfaction

63 Moderate impact

The supplied aggregate satisfaction average provides a broad signal, while the response volume determines how stable it appears. No comment-level evidence is available to assess repeated complaints or confirm intended-use experiences.

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Value for money

83 Highest impact

Useful active delivery supports favorable serving value. Each amino acid has a plausible role, though several small amounts reduce depth.

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Report analysis

Goals

Stress Relief
Stress Relief
Impact
Highest effect
B+ Goal FitB+ Strength of SupportB- CoverageB+ Formula Quality
Glycine · 250 mgGABA · 250 mgTheanine · 50 mg

GABA, glycine, theanine, taurine, and tyrosine create a broad amino-acid and inhibitory-signaling formula for calm and mental balance. The GABA amount is useful, while glycine and theanine are below stronger standalone targets.

All active amounts are individually stated, and black pepper extract may affect absorption without hiding the core doses. Evidence for oral GABA is mixed, and the uneven dosing means the formula provides more breadth than consistent depth across every pathway.

Study evidence
GABA Supportive 6 studies
Glycine Supportive 1 study
Taurine Supportive 5 studies
Theanine Supportive 16 studies
Sleep Support
Sleep Support
Impact
Moderate effect
C+ Goal FitC+ Strength of SupportC CoverageC- Formula Quality
Theanine · 50 mgGlycine · 250 mg

GABA, glycine, theanine, and taurine provide a calming amino-acid blend, while tyrosine may be activating for some users. The formula is relaxation focused but not specifically designed for circadian timing.

GABA reaches a useful amount, whereas glycine and theanine are far below stronger sleep targets. Clear individual amounts support assessment, but the overall depth is limited.

Study evidence
GABA Supportive 4 studies
Glycine Supportive 3 studies
Taurine Not classified

No linked studies yet.

Theanine Supportive 8 studies

Ingredients

IngredientAmount per serving
GABA
250 mg
L-Glycine
250 mg
L-Tyrosine
100 mg
Taurine
100 mg
L-Theanine
50 mg
Bioperine Nature's Thermonutrient
5 mg
Adults 18–50
Report overview
GABA · 250 mg OverallScore78
B- Active Ingredient Quality & BioavailabilityA- Dose, Safety & Label TransparencyB- Value

The formula provides a clearly disclosed GABA amount at the start of the preferred range. Its unbranded source and ordinary capsule are adequate rather than premium. A low serving cost gives it good value for a multi-ingredient calming blend.

View ingredientView products
Theanine · 50 mg OverallScore76
B+ Active Ingredient Quality & BioavailabilityA- Dose, Safety & Label TransparencyD+ Value

The 50 mg L-theanine amount is clearly disclosed and may provide mild support within the broader formula. Generic sourcing provides no added purity or standardization assurance. Pricing is premium for the active amount delivered.

View ingredientView products
Glycine · 250 mg OverallScore61
B- Active Ingredient Quality & BioavailabilityC+ Dose, Safety & Label TransparencyF Value

Clearly named L-glycine provides an isolated source, although no premium grade or purity certification is shown. Its 250 mg contribution is modest alone but works as part of the calming blend. High cost per gram limits value for anyone primarily seeking glycine.

View ingredientView products
Loading alternative details
83 Performance

GABA Soothe

Jarrow Formulas
Sensoril ashwagandha with 100 mg each of theanine and GABA is better targeted than the original's modest theanine, tyrosine, and taurine amounts. The concise formula uses relevant calming ingredients at useful amounts; combined calming ingredients may add to alcohol or sedative effects.
83 Performance

ZenMind

NutriCology
550 mg of GABA with 200 mg of branded Suntheanine is better targeted than the original's modest theanine, tyrosine, and taurine amounts. The two main calming ingredients are fully disclosed at substantial amounts; swallowed GABA has uncertain access to the brain and the combination may cause drowsiness.
78 Performance

Serenelle

Quality Of Life
Sensoril ashwagandha, 200 mg of theanine, PharmaGABA, and lemon balm is better targeted than the original's modest theanine, tyrosine, and taurine amounts. Branded ingredients and meaningful amounts create a well-defined stress-support formula; the serving is not especially economical.
76 Budget

GABA Calm

Source Naturals Serene Science
125 mg of GABA with small amounts of glycine, tyrosine, taurine, and magnesium costs less per serving while keeping the formula relevant to the original's goals. The convenient lozenge provides mild situational calming at very efficient serving value; the supporting ingredients remain lightly dosed.
76 Budget

GABA Calm Orange Flavor

Source Naturals
125 mg of GABA with glycine, N-acetyl tyrosine, taurine, and magnesium costs less per serving while keeping the formula relevant to the original's goals. The lozenge retains a multi-amino-acid approach at lower recurring cost; only GABA is present at a notable amount.
76 Budget

GABA Calm Orange Flavor

Source Naturals Serene Science
125 mg of GABA with small amounts of glycine, tyrosine, taurine, and magnesium costs less per serving while keeping the formula relevant to the original's goals. The lozenge keeps several of the original amino acids at a lower recurring cost; the supporting amounts are too small for meaningful glycine or mineral supplementation.
80 Value

L-Theanine 100 mg

Metabolic Maintenance
100 mg of branded Suntheanine with 300 mg of glycine offers a more balanced mix of ingredient quality and serving value than the original's modest theanine, tyrosine, and taurine amounts. The branded theanine gives calm-focus support in a simpler, easier-to-assess formula; glycine is too modest for strong standalone effects.
79 Value

Relax Magnesium Powder Berry

youtheory
300 mg of magnesium citrate with 100 mg each of GABA and theanine offers a more balanced mix of ingredient quality and serving value than the original's modest theanine, tyrosine, and taurine amounts. The concise powder combines physical relaxation and calm-focus support with clear amounts; magnesium citrate may loosen stools in sensitive users.
74 Value

Chewable GABA

NOW
500 mg of GABA with taurine, inositol, and theanine in a chewable offers a more balanced mix of ingredient quality and serving value than the original's modest theanine, tyrosine, and taurine amounts. The substantial GABA amount gives the formula a clear calming focus; the supporting actives are small and the carbohydrate base makes it less focused than a capsule.
Report alternatives

Sources

Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.

  1. Safety and Efficacy of Gamma-Aminobutyric Acid from Fermented Rice Germ in Patients with Insomnia Symptoms: A Randomized, Double-Blind Trial.
    Byun JI; Shin YY; Chung SE; Shin WC · Journal of clinical neurology (Seoul, Korea) · 2020
    Randomized trial40 participantsSleep Support forGABA
  2. Reduced γ-aminobutyric acid in occipital and anterior cingulate cortices in primary insomnia: a link to major depressive disorder?
    Plante DT; Jensen JE; Schoerning L; Winkelman JW · Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2012
    Case-control study40 participantsSleep Support forGABA
  3. Analysis of the Effects of Known Sleep-Support Supplements in Relation to Life Habits, Sleep Conditions, and Sleep Problems.
    Imafuku F; Yamamoto K; Tanaka E; Aoki R; Nishino S · Nutrients · 2023
    Randomized trial160 participantsSleep Support forGABA
  4. The effect of glycine administration on the characteristics of physiological systems in human adults: A systematic review.
    Soh J; Raventhiran S; Lee JH; Lim ZX; Goh J; Kennedy BK; Maier AB · GeroScience · 2024
    Systematic reviewSleep Support forGlycine
  5. New therapeutic strategy for amino acid medicine: glycine improves the quality of sleep.
    Bannai M; Kawai N · Journal of pharmacological sciences · 2012
    Narrative reviewSleep Support forGlycine
  6. The effects of glycine on subjective daytime performance in partially sleep-restricted healthy volunteers.
    Bannai M; Kawai N; Ono K; Nakahara K; Murakami N · Frontiers in neurology · 2012
    Clinical trial7 participantsSleep Support forGlycine
  7. Oral intake of γ-aminobutyric acid affects mood and activities of central nervous system during stressed condition induced by mental tasks.
    Yoto A; Murao S; Motoki M; Yokoyama Y; Horie N; Takeshima K; Masuda K; Kim M; Yokogoshi H · Amino acids · 2012
    Randomized trial63 participantsStress Relief forGABA
  8. GABA Supplementation, Increased Heart-Rate Variability, Emotional Response, Sleep Efficiency and Reduced Depression in Sedentary Overweight Women Undergoing Physical Exercise: Placebo-Controlled, Randomized Clinical Trial.
    Guimarães AP; Seidel H; Pires LVM; Trindade CO; Baleeiro RDS; Souza PM; Silva FGDE; Coelho DB; Becker LK; Oliveira EC · Journal of dietary supplements · 2024
    Randomized trial30 participantsStress Relief Sleep Support forGABA
  9. Comparison of the effects of two amino acids, Gamma-aminobutyric acid (GABA) and L-theanine, on sedation, anxiety, and cognition in preoperative surgical patients - A randomized controlled study.
    Deshpande SS; Kurdi M; Baiju A; Athira AS; Sarasamma AG; Gangadharan AK · Journal of anaesthesiology, clinical pharmacology · 2025
    Randomized trial168 participantsStress Relief forGABA Stress Relief forTheanine
  10. Oral supplementation with glycine reduces oxidative stress in patients with metabolic syndrome, improving their systolic blood pressure.
    Díaz-Flores M; Cruz M; Duran-Reyes G; Munguia-Miranda C; Loza-Rodríguez H; Pulido-Casas E; Torres-Ramírez N; Gaja-Rodriguez O; Kumate J; Baiza-Gutman LA; Hernández-Saavedra D · Canadian journal of physiology and pharmacology · 2014
    Randomized trial60 participantsStress Relief forGlycine
  11. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial.
    Hidese S; Ogawa S; Ota M; Ishida I; Yasukawa Z; Ozeki M; Kunugi H · Nutrients · 2020
    Randomized trial30 participantsSleep Support forTheanine
  12. Comparison Between Efficacy of Oral Melatonin and Oral L-theanine in Improving Sleep in Cancer Patients Suffering From Insomnia: A Randomised Double-blinded Placebo-controlled Study.
    Kurdi MS; As A; Ladhad DA; Mitragotri MV; Baiju A · Indian journal of palliative care · 2024
    Randomized trial120 participantsSleep Support forTheanine
  13. The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis.
    Bulman A; D'Cunha NM; Marx W; Turner M; McKune A; Naumovski N · Sleep medicine reviews · 2025
    Meta-analysis897 participants19 studies pooledSleep Support forTheanine
  14. In Search of a Safe Natural Sleep Aid.
    Rao TP; Ozeki M; Juneja LR · Journal of the American College of Nutrition · 2016
    Narrative reviewSleep Support forTheanine
  15. L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled trial.
    Sarris J; Byrne GJ; Cribb L; Oliver G; Murphy J; Macdonald P; Nazareth S; Karamacoska D; Galea S; Short A; Ee C; Birling Y; Menon R; Ng CH · Journal of psychiatric research · 2020
    Randomized trial46 participantsSleep Support forTheanine
  16. Relieving occupational fatigue by consumption of a beverage containing γ-amino butyric acid.
    Kanehira T; Nakamura Y; Nakamura K; Horie K; Horie N; Furugori K; Sauchi Y; Yokogoshi H · Journal of nutritional science and vitaminology · 2011
    Clinical trial30 participantsStress Relief forGABA
  17. Cortical gamma-aminobutyric acid and glutamate in posttraumatic stress disorder and their relationships to self-reported sleep quality.
    Meyerhoff DJ; Mon A; Metzler T; Neylan TC · Sleep · 2014
    Case-control study45 participantsStress Relief forGABA
  18. Protective and therapeutic effectiveness of taurine supplementation plus low calorie diet on metabolic parameters and endothelial markers in patients with diabetes mellitus: a randomized, clinical trial.
    Moludi J; Qaisar SA; Kadhim MM; Ahmadi Y; Davari M · Nutrition & metabolism · 2022
    Randomized trial120 participantsStress Relief forTaurine
  19. Effects of taurine supplementation on VDT work induced visual stress.
    Zhang M; Bi LF; Ai YD; Yang LP; Wang HB; Liu ZY; Sekine M; Kagamimori S · Amino acids · 2005
    Randomized trial25 participantsStress Relief forTaurine
  20. Taurine supplementation attenuates delayed increase in exercise-induced arterial stiffness.
    Ra SG; Choi Y; Akazawa N; Ohmori H; Maeda S · Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme · 2017
    Randomized trial29 participantsStress Relief forTaurine
  21. Correlations between dietary taurine intake and life stress in Korean college students.
    Sung MJ; Chang KJ · Advances in experimental medicine and biology · 2009
    Observational studyStress Relief forTaurine
  22. Profiling inflammatory and oxidative stress biomarkers following taurine supplementation: a systematic review and dose-response meta-analysis of controlled trials.
    Faghfouri AH; Seyyed Shoura SM; Fathollahi P; Shadbad MA; Papi S; Ostadrahimi A; Faghfuri E · European journal of clinical nutrition · 2022
    Meta-analysisStress Relief forTaurine
  23. Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial.
    White DJ; de Klerk S; Woods W; Gondalia S; Noonan C; Scholey AB · Nutrients · 2016
    Randomized trial34 participantsStress Relief forTheanine
  24. L-theanine relieves positive, activation, and anxiety symptoms in patients with schizophrenia and schizoaffective disorder: an 8-week, randomized, double-blind, placebo-controlled, 2-center study.
    Ritsner MS; Miodownik C; Ratner Y; Shleifer T; Mar M; Pintov L; Lerner V · The Journal of clinical psychiatry · 2011
    Randomized trial60 participantsStress Relief forTheanine
  25. Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial.
    Moulin M; Crowley DC; Xiong L; Guthrie N; Lewis ED · Neurology and therapy · 2024
    Randomized trial30 participantsStress Relief forTheanine
  26. A Randomized, Triple-Blind, Placebo-Controlled, Crossover Study to Investigate the Efficacy of a Single Dose of AlphaWave® L-Theanine on Stress in a Healthy Adult Population.
    Evans M; McDonald AC; Xiong L; Crowley DC; Guthrie N · Neurology and therapy · 2021
    Randomized trialStress Relief forTheanine