Investigating the effects of THC and d-limonene in healthy adults

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This clinical trial aims to explore how orally administered d-limonene interacts with delta-9-tetrahydrocannabinol (THC) in healthy adult volunteers. The study will assess whether d-limonene can modulate the effects of THC when both substances are taken orally, similar to previous findings with inhalation. Participants will undergo six outpatient drug administration sessions, receiving either placebo, THC alone, or varying doses of d-limonene combined with THC. The trial will recruit up to 20 participants who have prior experience with cannabis.

Why it matters

Who can join: the full rules

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 it's running

• Johns Hopkins Behavioral Pharmacology Research Unit
  Baltimore, Maryland, United States Recruiting

Study contacts

• Principal investigator: Austin Zamarripa, PhD — Johns Hopkins School of Medicine
• Study coordinator: Austin Zamarripa, PhD
• Email: czamarr2@jhmi.edu
• Phone: 410-550-6969

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.