Use of Cannabidiol for the Treatment of Anxiety: A Short Synthesis of Pre-Clinical and Clinical Evidence

Summary & key facts

This review looked at animal and human studies of cannabidiol (CBD) for anxiety. In animals, CBD often reduced anxiety-like behaviors at low or medium doses but sometimes increased anxiety at high doses. Small human studies and public-speaking tests suggest CBD might reduce anxiety in healthy people and in social anxiety disorder, but evidence is still preliminary. CBD is generally reported as well tolerated, with some studies finding no signs of abuse, yet more research is needed on proper doses, long-term effects, and differences between males and females.

Key facts:

• Pre-clinical (animal) studies often show a bell-shaped dose–response: CBD reduced anxiety-like behavior at low and intermediate doses, but higher doses could be anxiogenic (increase anxiety-like behavior).
• Preliminary human trials, including studies using public-speaking tasks and people with social anxiety disorder, suggest CBD may have anxiolytic (anxiety-reducing) effects, but these findings are early and limited.
• Most pre-clinical and clinical CBD studies reviewed were done using males only, so results may not apply equally to females and sex/gender differences are a noted research gap.
• CBD is generally described as safe and well tolerated in multiple studies. Some reports say chronic use and doses up to 1500 mg/day were tolerated in humans.
• The World Health Organization and several trials report that CBD shows little potential for abuse or dependence in humans, and many studies found no increase in subjective “high” or drug-liking after CBD. One study did report some intoxicat
• Current standard drug treatments for anxiety often help only about 40–60% of patients and have adverse effects, which is part of the reason researchers are studying CBD as a possible new option.
• Proposed biological actions of CBD relevant to anxiety include interaction with serotonin 5-HT1A receptors, CB1/CB2 cannabinoid receptors, TRPV1 channels, and indirect increases in the endocannabinoid anandamide by inhibiting the FAAH enzym
• The review concludes that more research is needed to determine whether CBD is effective across different anxiety disorders, what doses work best, and whether effects last over time.

Abstract

Anxiety disorders have the highest lifetime prevalence of any mental illness worldwide, leading to high societal costs and economic burden. Current pharmacotherapies for anxiety disorders are associated with adverse effects and low efficacy. Cannabidiol (CBD) is a constituent of the Cannabis plant, which has potential therapeutic properties for various indications. After the recent legalization of cannabis, CBD has drawn increased attention as a potential treatment, as the majority of existing data suggest it is safe, well tolerated, has few adverse effects, and demonstrates no potential for abuse or dependence in humans. Pre-clinical research using animal models of innate fear and anxiety-like behaviors have found anxiolytic, antistress, anticompulsive, and panicolytic-like effects of CBD. Preliminary evidence from human trials using both healthy volunteers and individuals with social anxiety disorder, suggests that CBD may have anxiolytic effects. Although these findings are promising, future research is warranted to determine the efficacy of CBD in other anxiety disorders, establish appropriate doses, and determine its long-term efficacy. The majority of pre-clinical and clinical research has been conducted using males only. Among individuals with anxiety disorders, the prevalence rates, symptomology, and treatment response differ between males and females. Thus, future research should focus on this area due to the lack of research in females and the knowledge gap on sex and gender differences in the effectiveness of CBD as a potential treatment for anxiety.

Topics

Cannabis and Cannabinoid Research Neurotransmitter Receptor Influence on Behavior

Categories

Health Sciences Medicine Pharmacology

Tags

Adverse effect Anxiety Anxiety disorder Anxiolytic Cannabidiol Cannabis Clinical psychology Clinical trial Internal medicine Medicine Pharmacology Psychiatry Social anxiety