Could a natural supplement quiet the distracted mind?
NCT ID NCT07777328
First seen Aug 20, 2026 · Last updated Aug 21, 2026 · Updated 1 time
Summary
This trial tests whether 5-HTP, a natural chemical that the body turns into serotonin, can reduce distractibility in adults with high levels of ADHD traits. Participants take either 5-HTP or a placebo and then perform tasks that measure eye movements and reaction time to see if they are less easily distracted. The goal is to gather initial evidence on whether 5-HTP could one day support people with attention problems.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- 5-hydroxytryptophan (5-HTP), a dietary supplement that the body converts into serotonin
- What this could lead to
- If 5-HTP reduces distractibility, it could point toward a natural supplement to help people with attention problems.
- What could go wrong
- This is an early, small trial. 5-HTP may not affect distractibility, and it can cause side effects like nausea. Results may not apply to everyone with ADHD.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
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Not a phased trial
Phase numbers describe drug development. The registry uses this when they do not apply, as it does for trials of devices, procedures or behaviour changes, and for observational studies.
- Participants
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About 150 people
The number the study aims to enrol. It can still change while the study runs.
- Started
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Nov 2025
- Expected to finish
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Jun 2027
An estimate. End dates often move.
- Lead sponsor
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Other sponsor
The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
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18 to 65 years
- Sex
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Anyone
- Healthy volunteers
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Accepted
You do not need to have the condition being studied to take part.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: * 18-65 years of age * Normal or corrected to normal vision with contact lenses. * Score of \<9 or \>14 on the ASRS v5 (assessed in pre screen questionnaire) Exclusion Criteria: * Current use of psychostimulant medication or medication for the treatment of ADHD * Current use of medications known to impact the serotonergic system (e.g., SSRIs). * Smoking or vaping * Pregnancy * Breast feeding * Lactose intolerance * Veganism * Dyslexia
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
How to take part
Only the study team decides who joins. These are the ways to reach them.
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The places running it
1 site. The list below names each one and where it is.
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The official record
ClinicalTrials.gov lists the study team's own contact details, including names and phone numbers. We don't republish those.
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A doctor treating you
A doctor who knows your case can contact a study site on your behalf, and can tell you whether this study is worth pursuing at all.
Contacts and locations
Locations
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University of Sheffield
RECRUITINGSheffield, South Yorkshire, S10 2TN, United Kingdom
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