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

Not Applicable

Completed

• Conditions: Theanine, (L)-Isomer
• Interventions: Dietary Supplement: L-theanine capsule; Dietary Supplement: Placebo capsule

• Registration Number: NCT01851122
• Lead Sponsor: The University of Texas Health Science Center, Houston

Brief Summary

The amino acid l-theanine (the active ingredient in green tea) is considered to have a calming effect without causing sleepiness. This study evaluates whether l-theanine affects blood pressure, heart rate, alertness, and sense of well-being.

Detailed Description

Not available

Study Timeline

• Study Start: 2011-11
• Primary Completion: 2012-10
• Study Completion: 2012-10
• Study First Submitted: 2013-05-03
• Study First Submitted QC: 2013-05-07
• Study First Posted: 2013-05-10
• Status Verified: 2023-12
• Last Update Submitted: 2023-12-05
• Last Update Posted: 2023-12-13

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 26

Inclusion Criteria

• adult
• able to swallow capsule

Exclusion Criteria

• none

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
L-theanine capsule	L-theanine capsule	-
Placebo capsule	Placebo capsule	-

Primary Outcome Measures

Name	Time	Method
Alertness	48 hrs	Degree of subjective alertness, measured on a visual analog scale
Well-Being	48 hrs	Sense of subjective well-being as measured on a visual analog scale

Trial Locations

Locations (1)

Physicians at Sugar Creek; 🇺🇸 Sugar Land, Texas, United States