Efficiency of Different Supplements in Alleviating Symptoms of ADHD with or Without the Use of Stimulants: A Systematic Review.

2025-04-28
Nutrients 17(9)
- Shatha Al Shahab
- Rawan Al Balushi
- Amna Qambar
- Ruqayah Abdulla
- Maryam Qader
- Shooq Abdulla
- Haitham Jahrami

PubMed: 40362791
DOI: 10.3390/nu17091482

Study Design

Type: Systematic Review
Methods: International databases (PubMed/MEDLINE and Scopus) were searched for English-language RCTs, open-label studies, and cross-sectional studies.

Rigorous Journal

Objective

This review aims to assess the efficacy and safety of different supplements, such as L-theanine, caffeine, Ginkgo biloba L., and Bacopa monnieri for improving ADHD symptoms, to determine the most effective supplement and provide insight for medical practice.

Methods

International databases (PubMed/MEDLINE and Scopus) were searched for English-language RCTs, open-label studies, and cross-sectional studies.

Results

Studies on L-theanine, caffeine, Ginkgo biloba L., and Bacopa monnieri have shown various effects on ADHD symptoms. L-theanine improved sleep efficiency but not other sleep parameters. Caffeine showed no significant benefits, although its combination with L-theanine may enhance attention. Bacopa monnieri consistently improved inattention, hyperactivity, and memory, whereas Ginkgo biloba L. reduced ADHD symptoms, particularly inattention, but was less effective than methylphenidate.

Conclusions

The evidence revealed the potential use of supplements as complementary ADHD treatments under clinical guidance. The limited effect of supplements cannot replace the well-documented efficacy of stimulants for ADHD treatment. Additional studies are needed to ascertain the most effective dosages and the safety of these supplements as adjunctive treatments for ADHD.

Research Insights

Bacopa→Improved Attention Span
Bacopa monnieri consistently improved inattention, hyperactivity, and memory
Effect
Beneficial
Effect size
Moderate
Bacopa→Improved Memory Function
Bacopa monnieri consistently improved inattention, hyperactivity, and memory
Effect
Beneficial
Effect size
Moderate
Bacopa→Reduced Hyperactivity
Bacopa monnieri consistently improved inattention, hyperactivity, and memory
Effect
Beneficial
Effect size
Moderate
Ginkgo→Improved Attention Span
Bacopa monnieri consistently improved inattention, hyperactivity, and memory
Effect
Beneficial
Effect size
Moderate
Ginkgo→Reduced ADHD Symptoms
Ginkgo biloba reduced ADHD symptoms, particularly inattention, but was less effective than methylphenidate.
Effect
Beneficial
Effect size
Small
L-Theanine→Improved Sleep Efficiency
L-theanine improved sleep efficiency but not other sleep parameters.
Effect
Beneficial
Effect size
Moderate