THC Titration with High-Potency Cannabis Concentrates

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

In this randomized crossover trial, 36 regular cannabis users will test concentrates with different THC levels (30%, 60%, and 90%) to see if they can adjust their intake to reach their preferred psychoactive effects. Researchers will measure subjective experiences, cognition, physiology, and pharmacokinetics to compare responses across potency levels. The design allows each participant to try multiple concentrations, helping to understand self-titration with high-potency products. The study is conducted at the Centre for Addiction and Mental Health in Toronto with collaboration from NIDA.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Age 19-55 years.
* Frequency of primary exposure to cannabis 1-4 occasions per week, through any route of administration, over the past three months; participants must report experience with vaping high-potency liquid concentrates with more than 3 exposures to 90% THC and willingness to use such products in the study.
* Refrain from cannabis for 48 hours and from alcohol for 12 hours before visits.
* Agree not to drive a car for 24 hours after each visit.
* Abstain from recreational drugs for at least 48 hours prior to each visit.
* Abstain from any drugs not medically required.
* Well-controlled blood pressure for participants with hypertension.

Exclusion Criteria:

* Pregnant/breastfeeding (women of childbearing potential must have a negative pregnancy test and report use of appropriate contraception).
* Evidence of cardiac arrhythmias/failure, ischaemic heart disease.
* Recent open heart/open chest surgery or cataract surgery.
* Evidence from Structured Clinical Interview for DSM-5 \[SCID-5-CT\] or clinical evaluation of lifetime psychotic disorder/schizophrenia or bipolar disorder; family history of a first-degree relative with a diagnosis of psychotic disorder or schizophrenia; history of psychiatric co-morbidities in the past year (major depression, anxiety disorder or suicide attempt in past year or current suicidal ideation) and current substance use disorder/dependence.
* Evidence of neurological illness (e.g., stroke, epilepsy, traumatic brain injury).
* Renal or hepatic abnormalities (self-report and blood hematology/chemistry); and
* Respiratory diseases, including asthma and physician-diagnosed lung disease.
* Taking prescribed medications that contain either THC or cannabidiol (CBD).
* Participation in another clinical or non-therapeutic study in the last three months.
* Bleeding disorders.

Where it's running

• Centre for Addiction and Mental Health
  Toronto, Ontario, Canada Recruiting

Study contacts

• Study coordinator: Sergio Rueda, PhD
• Email: sergio.rueda@camh.ca
• Phone: 416-535-8501

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• fMRI pilot: how THC affects memory and learning in young to middle-aged adults

  This will see if a single dose of THC temporarily impairs memory and learning in young to middle-aged adults who use cannabis.

  Recruiting Phase 2 Yale University · Hartford, Connecticut · NCT06647524

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

  This study is testing if a compound called d-limonene can change how THC affects healthy adults when both are taken together in a pill form.

  Recruiting Phase 1 Johns Hopkins University · Baltimore, Maryland · NCT06378957

• Exploring how CBD affects THC's psychoactive effects

  This study is testing how different amounts of CBD can change the effects of THC when people inhale them together.

  Recruiting Phase 1/2 Centre hospitalier de l'Université de Montréal (CHUM) · Montreal, Quebec · NCT06099379

• How marijuana (THC) and tobacco interact when used together

  This test tries to see if combining marijuana (THC) and tobacco changes blood drug levels and how people feel and respond physically in adults who regularly use both.

  Recruiting Phase 2 University of California, San Francisco · San Francisco, California · NCT05999383

• Effects of cannabis on the microbiome and inflammation in HIV

  This study is testing how cannabis compounds THC and CBD affect gut health and inflammation in people living with HIV.

  Recruiting Phase 2 University of California, San Diego · San Diego, California · NCT05514899

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.