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Neuroimaging of St. John's Wort-Induced Changes of Serotonin Metabolism in Normal Subjects
NCT00001919 · View on ClinicalTrials.gov ↗
Study Summary
St. John's Wort is a popular dietary supplement that many people take to elevate mood or relieve stress. This study will test in normal volunteers whether this preparation may alter mood and if so, by what means. Animal studies suggest that St. John's Wort may work similarly to some antidepressants that affect levels of the chemical serotonin in the brain. Participants in this study must also be enrolled in NIMH protocol #98-M-0094 (SPECT Imaging of Dopamine and Serotonin Transporters in Neuropsychiatric Patients and Normal Volunteers) and protocol #91-M-014 (MRI Imaging of Neuropsychiatric Patients and Controls). Separate consent forms are required for each study. Candidates will undergo medical and psychiatric evaluations that may include blood and urine tests, electroencephalogram and electrocardiogram. Normal volunteers will have a mood assessment at the beginning of the study. They will then be randomly assigned to take either placebo (a pill with no active ingredient) or St. John's Wort 3 times a day for 2 weeks, and will be told what they are taking. After an 11-week hiatus, they will again start treatment on the same schedule, but will not be told which preparation they are receiving. Each evening during the 2-week treatment periods, subjects will complete a brief self-rating mood assessment questionnaire. At the end of each treatment period, they will undergo SPECT brain imaging (a type of CT scan) to determine dopamine and serotonin distribution and density in the brain. For this procedure, study subjects take three drops of potassium iodide solution within 24 hours before the scan and two drops nightly for 3 days following the procedure. About 10 ml (less than two teaspoons) of blood are drawn before a radioactive tracer is injected. SPECT imaging is done the next day. After about 1 hour of imaging, subjects are given either a placebo or St. John's Wort, and then imaging continues for another 2 hours. During the procedure, up to five blood samples of 6
Conditions Studied
Interventions
- DRUG Hypericum (LI-160)
Study Locations (1)
Maryland
- National Institute of Mental Health (NIMH) — Bethesda
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 13 participants |
| Start Date | 1999-09 |
| Est. Completion | 2002-06 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT00001919
The ClinicalTrials.gov registry entry for NCT00001919 describes a study currently listed as completed. It is categorized as an unspecified phase, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 13 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is National Institute of Mental Health (NIMH), which has 317 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 2 conditions, with Healthy appearing as the primary indexed condition, and to 1 intervention — of which Hypericum (LI-160) is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT00001919 reports 1 study location spanning 1 distinct geographic area — top geographies include Maryland. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT00001919 about?
NCT00001919 is a clinical study titled "Neuroimaging of St. John's Wort-Induced Changes of Serotonin Metabolism in Normal Subjects". St. John's Wort is a popular dietary supplement that many people take to elevate mood or relieve stress. This study will test in normal volunteers whether this preparation may alter mood and if so, by what means. Animal studies suggest that St. John's Wort may work similarly to some antidepressants ...
What is the current status of trial NCT00001919?
This trial is currently completed. The enrollment target is 13 participants. The study started on 1999-09. Estimated completion is 2002-06.
What conditions does trial NCT00001919 study?
This clinical trial studies the following conditions: Healthy, Mood Disorder. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT00001919?
The interventions under investigation include: Hypericum (LI-160) (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT00001919?
This trial is sponsored by National Institute of Mental Health (NIMH), which has 317 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT00001919 being conducted?
This trial has 1 study location across Maryland. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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