A systematic review found limited but promising evidence for CBD in substance use, psychosis, and anxiety

Of 1,301 papers screened, only 27 met inclusion criteria for CBD in psychiatric disorders, with the strongest signals for substance use disorders, chronic psychosis, and anxiety, though the evidence remains insufficient for clinical recommendations.

Bonaccorso, Stefania et al.·Neurotoxicology·2019·Preliminary EvidenceSystematic Review
RTHC-01956Systematic ReviewPreliminary Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Systematic Review
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

From 1,301 screened papers, 27 met inclusion criteria (RCTs of CBD for psychiatric disorders). Limited evidence suggested potential therapeutic effects for substance use disorders, chronic psychosis, and anxiety. Evidence was insufficient for depression, PTSD, sleep, cognitive impairment, eating disorders, and other conditions.

Key Numbers

1,301 papers identified. 190 after abstract screening. 27 met inclusion criteria. Most promising: substance use disorders, chronic psychosis, anxiety. Insufficient evidence for depression, PTSD, sleep, cognition, eating disorders.

How They Did This

Systematic review following PRISMA guidelines, searching for RCTs of CBD for psychiatric conditions including substance use, psychosis, anxiety, mood, cognitive, sleep, personality, eating, OCD, PTSD, and somatic disorders.

Why This Research Matters

With CBD products increasingly marketed for mental health conditions, this systematic review provides a reality check: while some conditions show promise, the clinical trial base is tiny relative to the scale of CBD use for psychiatric symptoms.

The Bigger Picture

The contrast between 27 qualifying studies and millions of people using CBD for mental health highlights an enormous evidence-practice gap. The conditions where CBD shows the most promise (psychosis, substance use) are not the ones most consumers are targeting (anxiety, sleep, mood).

What This Study Doesn't Tell Us

Very few RCTs available. Heterogeneous CBD formulations and doses across studies. Most studies had small sample sizes. The systematic review could only assess what has been studied, leaving many conditions essentially unexamined.

Questions This Raises

  • ?Will larger RCTs confirm the signals for psychosis and substance use disorders?
  • ?Does CBD have any role in the conditions where evidence is currently lacking?
  • ?Could the absence of evidence reflect lack of study rather than lack of efficacy?

Trust & Context

Key Stat:
Only 27 qualifying studies
Evidence Grade:
Rated preliminary because despite rigorous systematic review methodology, the underlying evidence base is extremely limited.
Study Age:
Published in 2019. Additional CBD clinical trials have been conducted since.
Original Title:
Cannabidiol (CBD) use in psychiatric disorders: A systematic review.
Published In:
Neurotoxicology, 74, 282-298 (2019)
Database ID:
RTHC-01956

Evidence Hierarchy

Meta-Analysis / Systematic ReviewCombines many studies into one answer
This study
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Analyzes all available research on a topic using a structured method.

What do these levels mean? →

Frequently Asked Questions

Does CBD help with psychiatric conditions?

The strongest signals are for substance use disorders, chronic psychosis, and anxiety. However, only 27 clinical trials met quality criteria out of 1,301 papers screened, so the evidence remains limited for all conditions.

What about CBD for depression or sleep?

The review found insufficient evidence for CBD in depression, sleep disorders, PTSD, cognitive impairment, and most other psychiatric conditions. This does not necessarily mean CBD is ineffective, but it has not been adequately studied.

Read More on RethinkTHC

Cite This Study

RTHC-01956·https://rethinkthc.com/research/RTHC-01956

APA

Bonaccorso, Stefania; Ricciardi, Angelo; Zangani, Caroline; Chiappini, Stefania; Schifano, Fabrizio. (2019). Cannabidiol (CBD) use in psychiatric disorders: A systematic review.. Neurotoxicology, 74, 282-298. https://doi.org/10.1016/j.neuro.2019.08.002

MLA

Bonaccorso, Stefania, et al. "Cannabidiol (CBD) use in psychiatric disorders: A systematic review.." Neurotoxicology, 2019. https://doi.org/10.1016/j.neuro.2019.08.002

RethinkTHC

RethinkTHC Research Database. "Cannabidiol (CBD) use in psychiatric disorders: A systematic..." RTHC-01956. Retrieved from https://rethinkthc.com/research/bonaccorso-2019-cannabidiol-cbd-use-in

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.