Cannabigerol Oil for Adolescents With ADHD (CAN-ADHD) (CAN-ADHD)

Potential Effects of Cannabigerol in Adolescents With Attention-Deficit/Hyperactivity Disorder: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial (CAN-ADHD)

This study aims to evaluate the potential effects of full-spectrum cannabigerol (CBG) oil on cognitive and behavioral symptoms in adolescents diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD). ADHD is a neurodevelopmental disorder characterized by inattention, hyperactivity, and impulsivity, often associated with impairments in academic, social, and emotional functioning.

This is a randomized, double-blind, placebo-controlled clinical trial with a parallel design. A total of 60 adolescents aged 12 to 17 years, diagnosed with ADHD and with insufficient response to previous treatments, will be enrolled and randomly assigned to either the intervention group or the placebo group.

Participants in the intervention group will receive full-spectrum CBG oil (30 mg/mL), administered sublingually, with individualized dosing determined by the study physician and adjusted through weekly monitoring. The placebo group will receive an inert oil matched in appearance and administration conditions.

The intervention will last for 12 weeks, including in-person clinical assessments at baseline, week 6, and week 12, as well as weekly remote monitoring to assess adherence, safety, and dose adjustments.

Primary outcomes will include changes in ADHD symptom severity measured by the SNAP-IV scale. Secondary outcomes will assess quality of life, emotional symptoms, sleep patterns, and safety profile.

This study aims to contribute to the scientific understanding of cannabinoids as a potential therapeutic option for adolescents with ADHD, a population for which current evidence remains limited.

Study Overview

• Status: Recruiting
• Conditions: Attention-Deficit/Hyperactivity Disorder (ADHD)
• Intervention / Treatment: Drug: Experimental: Full-spectrum CBG oil 30 mg/mL; Drug: Placebo oil (MCT oil)

Detailed Description

Attention-Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by persistent symptoms of inattention, hyperactivity, and impulsivity that interfere with academic performance, emotional regulation, social functioning, and quality of life. ADHD is one of the most prevalent neurodevelopmental conditions worldwide and may persist from childhood into adolescence and adulthood. In addition to the core symptoms, individuals with ADHD frequently present emotional dysregulation, sleep disturbances, anxiety symptoms, impaired executive functioning, and psychosocial difficulties that significantly affect both patients and their families.

Current treatment strategies for ADHD include pharmacological and non-pharmacological interventions, with stimulant medications representing the first-line pharmacotherapy in most clinical guidelines. Although these treatments are effective for many patients, a substantial proportion of adolescents experience insufficient clinical response, limited tolerability, adverse effects, or difficulties with long-term adherence. This scenario reinforces the need for investigating alternative and complementary therapeutic approaches capable of targeting both behavioral and emotional dimensions associated with ADHD.

The endocannabinoid system has emerged as a potential target in neuropsychiatric disorders due to its involvement in emotional regulation, cognition, attention, stress response, sleep modulation, and synaptic plasticity. Cannabis-derived compounds have demonstrated neurobiological effects that may influence pathways relevant to ADHD symptomatology. Among these compounds, cannabigerol (CBG) has attracted increasing scientific interest. CBG is a non-intoxicating phytocannabinoid that acts on multiple molecular targets, including cannabinoid receptors, adrenergic pathways, serotonergic signaling, and transient receptor potential channels. Preclinical and observational evidence suggests potential anxiolytic, neuroprotective, anti-inflammatory, and neuromodulatory properties, although controlled clinical evidence remains scarce, particularly in pediatric and adolescent populations.

This study was designed to evaluate the potential effects and safety profile of a full-spectrum cannabigerol-based formulation in adolescents with ADHD. The study consists of a randomized, double-blind, placebo-controlled clinical trial with a parallel-group design. A total of 60 adolescents aged between 12 and 17 years with a previous diagnosis of ADHD will be enrolled and randomly assigned in a 1:1 ratio to either the intervention group or the placebo group.

Participants allocated to the intervention group will receive a full-spectrum Cannabis sativa extract containing cannabigerol (CBG) 30 mg/mL, cannabidiol (CBD) 30 mg/mL, and tetrahydrocannabinol (THC) 3 mg/mL. The formulation will be administered sublingually according to a structured dose titration schedule beginning with low doses and gradually increasing over the first weeks of treatment. From week six onward, dose adjustments may be performed according to clinical response and tolerability, respecting predefined safety limits established in the protocol. Participants allocated to the placebo group will receive a formulation based on medium-chain triglyceride (MCT) oil matched in appearance, color, viscosity, and administration schedule to preserve blinding conditions.

The total intervention period will last 12 weeks. Participants will undergo clinical assessments at baseline, week 6, and week 12. In addition, weekly remote monitoring will be conducted throughout the study to assess treatment adherence, adverse effects, tolerability, and general clinical evolution. Medical follow-up will be performed by trained physicians involved in the research team.

The primary outcome of the study will be the change in ADHD symptom severity assessed through the SNAP-IV (Swanson, Nolan and Pelham Questionnaire, version IV). Secondary outcomes will evaluate quality of life, emotional symptoms, sleep patterns, and safety profile using validated instruments, including the KINDL (Children and Adolescents Quality of Life Questionnaire), WHOQOL-BREF (World Health Organization Quality of Life - Brief Version), DASS-21 (Depression Anxiety and Stress Scale), and CSHQ (Child Sleep Habits Questionnaire).

This study aims to contribute to the advancement of clinical evidence regarding cannabinoid-based interventions in ADHD, particularly involving CBG-rich formulations in adolescents. By using a randomized, double-blind, placebo-controlled design, the study seeks to generate scientifically rigorous data regarding efficacy, tolerability, and safety, potentially supporting future therapeutic strategies and expanding knowledge about the role of the endocannabinoid system in neurodevelopmental disorders.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Rafael Mariano Bitencourt, PhD; Phone Number: +55 48 9 8833-6460; Email: bitencourtrm@gmail.com

Study Locations

• Brazil
  • Santa Catarina
    • Tubarão, Santa Catarina, Brazil, 88704900
      • Recruiting
      • Universidade do Sul de Santa Catarina - UNISUL
      • Contact: Rafael Mariano Bitencourt, PhD; Phone Number: +55 48 9 8833-6460; Email: bitencourtrm@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adolescents aged 12 to 17 years
• Diagnosis of Attention-Deficit/Hyperactivity Disorder (ADHD) confirmed using the SNAP-IV (Swanson, Nolan and Pelham Questionnaire, version IV)
• History of previous treatment with pharmacological or non-pharmacological interventions without significant improvement of symptoms
• Absence of severe psychiatric disorders or relevant physical comorbidities
• Ability of the participant and legal guardian to understand study procedures
• Provision of written informed consent by the legal guardian and assent by the adolescent

Exclusion Criteria:

• Use of cannabinoid-based substances (natural or synthetic) within 30 days prior to study initiation
• History of intolerance or adverse reactions to cannabis-derived compounds (e.g., confusion, paranoia, pruritus, excessive drowsiness, vomiting, diarrhea, or seizures)
• Presence of any significant physical comorbidity
• Presence of severe psychiatric disorder not related to ADHD
• Moderate to severe cognitive impairment
• Inability or unwillingness to complete study procedures or questionnaires adequately

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Full-spectrum CBG oil 30 mg/mL; Participants allocated to this arm will receive sublingual administration of full-spectrum cannabigerol oil for 12 weeks under double-blind conditions. The formulation contains cannabigerol, cannabidiol, and a low concentration of tetrahydrocannabinol. Clinical assessments will be performed at baseline, Week 6, and Week 12, with weekly remote monitoring to evaluate adherence, tolerability, adverse events, and the need for dose adjustments.	Drug: Experimental: Full-spectrum CBG oil 30 mg/mL; Full-spectrum Cannabis sativa extract containing cannabigerol (CBG) 30 mg/mL, cannabidiol (CBD) 30 mg/mL, and tetrahydrocannabinol (THC) 3 mg/mL, administered sublingually for 12 weeks according to a structured dose titration schedule. Treatment will begin with low doses and may be gradually adjusted based on clinical response and tolerability, respecting predefined safety limits established in the study protocol.
Placebo Comparator: Placebo (MCT oil); Participants allocated to this arm will receive sublingual administration of placebo oil for 12 weeks under double-blind conditions. The placebo formulation consists of medium-chain triglyceride (MCT) oil matched to the experimental product in appearance, viscosity, color, and administration schedule. Clinical assessments will be performed at baseline, Week 6, and Week 12, with weekly remote monitoring to evaluate adherence, tolerability, adverse events, and the need for dose adjustments.	Drug: Placebo oil (MCT oil); Placebo comparator consisting of medium-chain triglyceride (MCT) oil administered sublingually for 12 weeks according to the same dose titration schedule used in the experimental group. The placebo formulation is matched to the active intervention in appearance, color, viscosity, packaging, and administration conditions to maintain blinding throughout the study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Attention-Deficit/Hyperactivity Disorder symptom severity assessed by the Swanson, Nolan and Pelham Questionnaire, version IV	Evaluation of longitudinal changes in Attention-Deficit/Hyperactivity Disorder symptom severity using the Swanson, Nolan and Pelham Questionnaire, version IV. The Attention-Deficit/Hyperactivity Disorder symptom score includes 18 core items rated from 0 to 3, with total scores ranging from 0 to 54. Higher scores indicate greater symptom severity.	Baseline, Week 6, and Week 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in quality of life of legal guardians assessed by the 36-Item Short Form Health Survey	Evaluation of longitudinal changes in legal guardians' quality of life using the 36-Item Short Form Health Survey. Scores are transformed into eight domain scores ranging from 0 to 100, with higher scores indicating better health-related quality of life.	Baseline, Week 6, and Week 12
Change in emotional symptoms assessed by the Depression Anxiety and Stress Scale for Children	Evaluation of longitudinal changes in symptoms of depression, anxiety, and stress using the Depression Anxiety and Stress Scale for Children. Total scores range from 0 to 63, with higher scores indicating greater emotional symptom severity.	Baseline, Week 6, and Week 12
Change in sleep patterns assessed by the Children's Sleep Habits Questionnaire	Evaluation of longitudinal changes in sleep behavior using the Children's Sleep Habits Questionnaire. Total scores range from 33 to 99, with higher scores indicating more sleep problems.	Baseline, Week 6, and Week 12
Number of participants with treatment-related adverse events assessed by the study adverse effects questionnaire	Assessment of safety through the number of participants reporting adverse events using the study adverse effects questionnaire. Each adverse event is recorded as present or absent, and severity is classified as mild, moderate, or intense. A higher number of reported adverse events indicates worse tolerability.	Weekly monitoring during 12 weeks and clinical assessments at Baseline, Week 6, and Week 12

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of missed doses reported during weekly remote monitoring	Assessment of treatment adherence based on caregiver reports during weekly remote monitoring. The outcome will be reported as the number of missed doses during the 12-week intervention period. A higher number of missed doses indicates lower treatment adherence.	Weekly during 12 weeks
Number of participants requiring dose adjustment during the intervention period	Assessment of dose adjustment patterns based on weekly remote monitoring and clinical evaluation. The outcome will be reported as the number of participants requiring dose reduction, delay in titration, or dose increase during the 12-week intervention period.	Weekly during 12 weeks

Collaborators and Investigators

• Sponsor: Universidade do Sul de Santa Catarina
• Collaborators: Associação Brasileira de Cannabis Medicinal

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): December 18, 2026
• Study Completion (Estimated): December 18, 2026

Study Registration Dates

• First Submitted: May 6, 2026
• First Submitted That Met QC Criteria: May 13, 2026
• First Posted (Actual): May 18, 2026

Study Record Updates

• Last Update Posted (Actual): May 18, 2026
• Last Update Submitted That Met QC Criteria: May 13, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Adolescents; ADHD; Cannabinoids; Cannabigerol
• Additional Relevant MeSH Terms: Mental Disorders; Neurodevelopmental Disorders; Attention Deficit and Disruptive Behavior Disorders; Attention Deficit Disorder with Hyperactivity
• Other Study ID Numbers: CEP-8.184.472

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No