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Showing 1–21 of 21 matching trials from the live ClinicalTrials.gov search.
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Completed Not applicable Interventional Accepts healthy volunteers

The Effect of the Amino Acid L-Theanine on Alertness and Vigilance

NCT01851122
Conditions
Theanine, (L)-Isomer
Interventions
L-theanine capsule, Placebo capsule
Dietary Supplement
Lead sponsor
The University of Texas Health Science Center, Houston
Other
Eligibility
18 Years and older
Enrollment
26 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2011 – 2012
U.S. locations
1
States / cities
Sugar Land, Texas
Completed Early Phase 1 Interventional Accepts healthy volunteers Results available

Effects of L-theanine on Motor Cortex Excitability in Healthy Subjects: A Paired-Pulse TMS Study

NCT04749745
Conditions
Cortical Excitability, Psychiatric Disorder
Interventions
L-theanine, Placebo
Drug
Lead sponsor
Butler Hospital
Other
Eligibility
18 Years to 65 Years
Enrollment
11 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2021
U.S. locations
1
States / cities
Providence, Rhode Island
Conditions
Attention Deficit Hyperactivity Disorder
Interventions
L-theanine, Caffeine, L-theanine-Caffeine Combination, Placebo
Dietary Supplement · Other
Lead sponsor
Texas Tech University
Other
Eligibility
8 Years to 17 Years · Male only
Enrollment
6 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2018
U.S. locations
1
States / cities
Lubbock, Texas
Conditions
Hematopoietic and Lymphatic System Neoplasm, Malignant Solid Neoplasm
Interventions
Survey Administration, Theanine
Other · Drug
Lead sponsor
City of Hope Medical Center
Other
Eligibility
18 Years and older
Enrollment
50 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2026 – 2027
U.S. locations
4
States / cities
Duarte, California • Huntington Beach, California • Irvine, California
Completed Not applicable Interventional Accepts healthy volunteers

The Poweroff Sleep Study

NCT03364101
Conditions
Sleep
Interventions
Placebo Capsule, POWEROFF Capsule
Dietary Supplement
Lead sponsor
NYU Langone Health
Other
Eligibility
18 Years to 65 Years
Enrollment
60 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2017 – 2018
U.S. locations
1
States / cities
New York, New York
Conditions
Attention, Mood
Interventions
Cranberry Juice Product
Dietary Supplement
Lead sponsor
Ocean Spray Cranberries, Inc.
Industry
Eligibility
18 Years to 45 Years
Enrollment
25 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2021
U.S. locations
1
States / cities
Chicago, Illinois
Conditions
Cognitive Performance
Interventions
L-theanine, Caffeine supplement, N1 app
Drug · Dietary Supplement · Device
Lead sponsor
Icahn School of Medicine at Mount Sinai
Other
Eligibility
18 Years and older
Enrollment
57 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2019 – 2020
U.S. locations
1
States / cities
New York, New York
Conditions
Sleep, Sleep Disturbance, Sleep Hygiene
Interventions
Beam Organics Dream Powder, Beam Organics Dream Powder Extra Strength, Placebo
Dietary Supplement
Lead sponsor
Beam
Industry
Eligibility
24 Years to 50 Years
Enrollment
64 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2022
U.S. locations
1
States / cities
Santa Monica, California
Recruiting Not applicable Interventional Accepts healthy volunteers

Evaluating SleepWhale Drops for Rest & Resilience

NCT07298161
Conditions
Sleep
Interventions
SleepWhale Natural Sleep Drops
Dietary Supplement
Lead sponsor
Efforia, Inc
Industry
Eligibility
Not listed
Enrollment
100 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
New York, New York
Conditions
Attention Deficit Hyperactivity Disorder (ADHD), Autism Spectrum Disorder (ASD)
Interventions
L-theanine and paraxanthine, Placebo
Dietary Supplement
Lead sponsor
Texas Tech University Health Sciences Center
Other
Eligibility
Male only
Enrollment
17 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2025 – 2026
U.S. locations
1
States / cities
Lubbock, Texas
Conditions
Stress
Interventions
Theanine Formulation, Placebo
Dietary Supplement
Lead sponsor
Supplement Formulators, Inc.
Industry
Eligibility
21 Years to 65 Years
Enrollment
14 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2022
U.S. locations
1
States / cities
Fort Lauderdale, Florida
Completed Not applicable Interventional Accepts healthy volunteers

Theanine and Caffeine on Neurophysiology of Attention

NCT02770105
Conditions
L-theanine
Interventions
Theanine, Caffeine, Theanine-Caffeine Combination, Placebo
Other
Lead sponsor
Texas Tech University
Other
Eligibility
18 Years to 60 Years · Male only
Enrollment
9 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016
U.S. locations
1
States / cities
Lubbock, Texas
Completed Not applicable Interventional Accepts healthy volunteers

Supplement Combination on Stress and Sleep

NCT06889584
Conditions
Healthy
Interventions
All Active Supplement Combinations (Ashwagandha, Rhodiola rosea, magnesium threonate, L-theanine, and apigenin)), AM Active Supplement Combination (Ashwagandha and Rhodiola rosea), PM Active Supplement Combination (Magnesium threonate, L-theanine, and apigenin), AM and PM Placebo
Combination Product · Other
Lead sponsor
University of South Carolina
Other
Eligibility
18 Years to 50 Years
Enrollment
115 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
Columbia, South Carolina
Completed Not applicable Interventional Accepts healthy volunteers

Impact of Supplements on Stress Markers

NCT05592561
Conditions
Physiological Stress
Interventions
mental stress task
Other
Lead sponsor
Texas State University
Other
Eligibility
18 Years to 40 Years
Enrollment
109 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2022 – 2023
U.S. locations
1
States / cities
San Marcos, Texas
Conditions
Anxiety, Stress
Interventions
Alcohol Alternative Herbal Tincture (Test Product), Placebo
Dietary Supplement
Lead sponsor
Apothekary
Industry
Eligibility
21 Years to 65 Years
Enrollment
80 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2024
U.S. locations
1
States / cities
Santa Monica, California
Conditions
Healthy
Interventions
Placebo, Dietary Supplement with actives
Dietary Supplement
Lead sponsor
Olly, PBC
Industry
Eligibility
5 Years to 14 Years
Enrollment
80 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025
U.S. locations
1
States / cities
Fair Lawn, New Jersey
Conditions
Absorption, Pharmacokinetic
Interventions
Hydration Multiplier + Energy, Hydration Multiplier + Sleep, Energy Comp, Sleep Comp
Dietary Supplement · Other
Lead sponsor
Liquid I.V.
Other
Eligibility
18 Years to 55 Years
Enrollment
37 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2023 – 2024
U.S. locations
1
States / cities
Raritan, New Jersey
Conditions
ADHD, Attention Difficulties, Mood, Anxiety, Caffeine
Interventions
Proper Wild energy shot
Other
Lead sponsor
Proper Wild, Inc.
Industry
Eligibility
18 Years to 55 Years
Enrollment
40 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2023
U.S. locations
1
States / cities
Santa Monica, California
Conditions
Stress
Interventions
Theanine for stress relief formulation, Placebo
Dietary Supplement
Lead sponsor
Supplement Formulators, Inc.
Industry
Eligibility
21 Years to 65 Years
Enrollment
104 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2023 – 2025
U.S. locations
1
States / cities
Fort Lauderdale, Florida
Conditions
Mental Fatigue
Interventions
Caffeine Blend, Sugar Pill
Dietary Supplement · Other
Lead sponsor
University of Mary Hardin-Baylor
Other
Eligibility
18 Years to 25 Years · Male only
Enrollment
31 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2016
U.S. locations
1
States / cities
Belton, Texas
Conditions
Physical Performance, Exercise Performance, Endurance Exercise, Perceived Exertion, Mood, Energy
Interventions
proprietary pre-workout supplement, Control placebo
Dietary Supplement
Lead sponsor
Applied Science & Performance Institute
Industry
Eligibility
18 Years to 55 Years
Enrollment
27 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
Tampa, Florida