The better-known child study focused on sleep
FDA reviewed a trial in 98 boys aged 8 to 12 that used 200 mg twice daily for six weeks. It identified problems with endpoint specification and analysis, and noted that reported comparisons did not meet the stated stricter significance threshold. This government assessment does not establish an ADHD-treatment dose. [1]
Sleep findings are not core symptom treatment
Improving a sleep measure, if confirmed, would not automatically demonstrate improved inattention, hyperactivity or daily functioning. The FDA assessment also discusses very small experiments involving theanine and caffeine; those are insufficient for a general pediatric regimen. [1]
Healthy-adult attention studies do not define adult ADHD care
A recent meta-analysis found selected short-term attention-task effects in healthy adults. That does not establish effectiveness in adults diagnosed with ADHD, long-term functional benefit or compatibility with a specific stimulant prescription. [2]
Keep the clinician involved in any supplement decision
Imagine a parent sees 400 mg daily in a study and considers giving that amount to a child. Age, other medicines, sleep problems and the actual treatment goal require professional review. Do not replace or adjust established ADHD care based on that research dose. [1][3]
| Population or outcome | Evidence boundary |
|---|---|
| Boys in a sleep trial | Not a general child ADHD dose |
| Healthy adult attention task | Not adult ADHD treatment |
| Caffeine combination pilot | Not a proven long-term regimen |
| Personal medication plan | Requires treating-clinician review |
Sources for this article
- FDA Pharmacy Compounding Advisory Committee October 29 2024 briefing materials
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product. - Cognitive and affective effects of L-Theanine: a systematic review and meta-analysis of 31 randomized trials.
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product. - Dietary Supplements: What You Need to Know
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product.