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Study on Cannabidiol and Aripiprazole for Treating Substance-Induced Psychosis in Young Patients

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effects of cannabidiol (CBD) as an additional treatment for young patients experiencing Substance-Induced Psychosis, a condition where drug use leads to symptoms of psychosis, such as hallucinations or delusions. The study will also involve patients with Cannabis Use Disorder, which is characterized by a problematic pattern of cannabis use leading to significant impairment or distress. The trial will compare the effects of CBD with a placebo, alongside the use of aripiprazole, an antipsychotic medication. Aripiprazole will be administered in different forms, including oral solutions and tablets, as well as long-acting injections.

The purpose of the study is to determine if CBD can help reduce the symptoms of cannabis use relapse in patients who are already receiving antipsychotic treatment. Participants will be randomly assigned to receive either CBD or a placebo, in addition to their regular antipsychotic medication. The study will last for six months, during which participants will be monitored for changes in their symptoms and overall health. Regular assessments will be conducted to track the progress of each participant, and the results will be analyzed to see if there is a significant difference between the group receiving CBD and the group receiving the placebo.

Throughout the study, participants will continue their treatment with aripiprazole, which may be switched from oral to long-acting injection form. The trial aims to provide insights into whether CBD can be a beneficial addition to existing treatments for young individuals dealing with substance-induced psychosis and cannabis use disorder. The findings could potentially lead to improved treatment strategies for managing these conditions.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Enrollment

    Upon joining the study, the participant will be required to provide a signed informed consent. If the participant is under 18, a parent or legal guardian must sign.

    A pregnancy test will be conducted for women of childbearing age before starting the treatment and periodically every 25 to 30 days.

  2. Step 2

    Initial treatment phase

    Participants will continue their current treatment with oral aripiprazole for a period ranging from 2 weeks to 6 months. This is to ensure there are no side effects before switching to a different form of the medication.

  3. Step 3

    Transition to long-acting treatment

    The oral aripiprazole will be replaced with an intramuscular injection of long-acting aripiprazole. This change is part of the study protocol.

  4. Step 4

    Cannabidiol treatment

    Participants will receive cannabidiol (CBD) as an additional treatment. The study aims to evaluate its effectiveness in reducing symptoms of cannabis use relapse.

    The treatment will be administered for a total duration of 6 months.

  5. Step 5

    Assessment and monitoring

    Every 28 days, participants will complete a questionnaire called the Addiction Severity Index (ASI) to assess symptoms related to cannabis use.

    The scores from these assessments will be collected and analyzed to compare the effects of CBD with a placebo.

  6. Step 6

    End of treatment evaluation

    At the end of the 6-month treatment period, a final evaluation will be conducted to assess the overall impact of the CBD treatment compared to the placebo group.

    The study will analyze changes in clinical symptoms, cognitive performance, and brain connectivity.

Who can join the trial?

11 criteria

  • The patient or their parent/legal guardian must sign a form to show they understand the study and agree to participate. This is called informed consent.
  • Women who can have children must take a pregnancy test before starting the study and regularly during the study. This is because the treatment might affect pregnancy.
  • The patient must switch from taking aripiprazole by mouth to receiving it as an injection. Aripiprazole is a medication used to treat certain mental health conditions.
  • Patients must use very effective birth control methods as recommended by health guidelines.
  • An identified person, like a family member or friend, must sign a form to acknowledge their responsibilities in the study.
  • The patient must be between 15 and 25 years old.
  • The patient must have a clinical diagnosis of Substance-Induced Psychosis, which is a mental health condition caused by substance use, according to the DSM-5, a manual used by healthcare professionals.
  • The patient must have a clinical diagnosis of Cannabis Use Disorder, which means having problems due to cannabis use, according to the DSM-5.
  • The patient must have used cannabis heavily in the last six months, showing six or more symptoms of Cannabis Use Disorder.
  • The patient must have been taking oral aripiprazole for at least two weeks and no more than six months before joining the study to ensure there are no side effects.
  • The symptoms must have started less than five years ago.

Who cannot join the trial?

7 criteria

  • Individuals who do not meet the criteria for **Cannabis Use Disorder** or **Substance-Induced Psychotic Disorder**. These are specific conditions related to the use of cannabis and its effects on mental health.
  • Individuals who are not within the specified age range for the study. The study is focused on a particular age group.
  • Individuals who are not able to follow the study procedures, such as attending regular assessments or completing questionnaires.
  • Individuals who have other medical conditions that might interfere with the study or its results.
  • Individuals who are currently participating in another clinical trial. This is to ensure that the results are not affected by other treatments.
  • Individuals who are pregnant or breastfeeding, as the study may not be safe for them or their babies.
  • Individuals who have a history of severe allergic reactions to any of the study medications or their components.
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Investigated drugs

Cannabidiol (CBD) is being tested as an additional treatment for young patients who have both substance abuse issues and psychosis. The study aims to see if CBD can help reduce symptoms of cannabis use relapse when used alongside standard antipsychotic medications. Participants will be assessed regularly to track any changes in their symptoms over a six-month period.

What is already known about the treatment

Cannabidiol – Cannabidiol, commonly known as CBD, is administered orally and is being studied as an add-on treatment for substance-induced psychosis, particularly in juvenile patients with cannabis use disorder. Currently, it is under investigation in clinical trials to assess its effectiveness in reducing symptoms of cannabis abuse relapse when used alongside traditional antipsychotic medications. CBD is believed to work by interacting with the endocannabinoid system in the brain, which may help regulate mood and perception. It is classified as a cannabinoid, a type of compound found in cannabis plants.

Investigated diseases

Substance-Induced Psychosis – This condition occurs when a person experiences psychotic symptoms as a direct result of substance use, such as drugs or alcohol. The symptoms can include hallucinations, delusions, and disorganized thinking. These symptoms typically appear during or shortly after substance use and can vary in intensity. The progression of the condition depends on the type and amount of substance used, as well as the individual's response to the substance. In some cases, symptoms may resolve after the substance is cleared from the body, while in others, they may persist for a longer period. The condition is often associated with substances like cannabis, alcohol, and stimulants.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-514393-44-00Protocol codeCAT-PSYEstimated enrolment60 patientsSponsorFondazione IRCCS Ca Granda Ospedale Maggiore Policlinico

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).