NCT06378957 · Johns Hopkins University
Behavioral Pharmacology of Orally Administered THC and D-limonene
What this study is about
The current clinical trial will investigate the effects of taken by mouth administered d-limonene (limonene), delta-9-tetrahydrocannabinol (THC) and the combination in healthy adult volunteers.
View original scientific description
The current clinical trial will investigate the effects of orally administered d-limonene (limonene), delta-9-tetrahydrocannabinol (THC) and the combination in healthy adult volunteers.
Interventions
DRUG
D-Limonene
Oral Limonene administered via capsule
DRUG
Delta-9-THC
Oral delta-9-THC in ethanol vehicle administered via capsule
DRUG
Placebo
Placebo (cellulose) administered via capsule
Primary outcome measures
Subjective Drug Effect as assessed by Visual Analog Scale
Time frame: 8 hours after dosing
Subjective drug effect will be measured on a 100 point visual analog scale (VAS) where 0 = no drug effect and 100 = strongest drug effect imaginable
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Have provided written informed consent
- Be between the ages of 21 and 55
- Be in good general health based on a physical examination, medical history, vital signs, and screening urine and blood tests
- Test negative for drugs of abuse other than cannabis, including breath alcohol at the screening visit and at clinic admission
- Not be pregnant or nursing (if female). All females must have a negative serum pregnancy test at the screening visit and a negative urine pregnancy test at clinic admission.
- Have a body mass index (BMI) in the range of 18 to 36 kg/m2
- Blood pressure at Screening Visit does not exceed a systolic blood pressure (SBP) of 150 mmHg or a diastolic blood pressure (DBP) of 90 mmHg
- Have no allergies to any of the ingredients used to prepare (cellulose, THC, d-limonene).
- Report having used a high THC cannabis product in the past 3 years and having experienced anxiety after consuming cannabis at least once in lifetime.
Exclusion criteria
- Non-medical use of psychoactive drugs other than, nicotine, alcohol, or caffeine 3 month prior to the Screening Visit;
- History of or current evidence of significant medical (e.g. seizure disorder) or psychiatric illness (e.g. psychosis) judged by the investigator to put the participant at greater risk of experiencing an adverse event due to exposure or completion of other study procedures.
- Use of an over the counter (OTC), systemic or topical drug(s), herbal supplement(s), or vitamin(s) within 14 days of experimental sessions; which, in the opinion of the investigator or sponsor, will interfere with the study result or the safety of the subject.
- Use of a prescription medication (with the exception of birth control prescriptions) within 14 days of experimental sessions; which, in the opinion of the investigator or sponsor, will interfere with the study result or the safety of the subject.
- Average use of cannabis more than 2 times per week in the prior 3 months.
- History of clinically significant cardiac arrhythmias or vasospastic disease (e.g., Prinzmetal's angina).
- Enrolled in another clinical trial or have received any drug as part of a research study within 30 days prior to dosing.
- Individuals with anemia or who have donated blood in the prior 30 days
Where
- Baltimore, Maryland
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 28, 2026 · Source of record for eligibility and locations