Cannabis Can Quell Anxiety

The cannabis plant contains more than 140 pharmacologically active cannabinoids, with cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) being the most dominant. Although CBD and THC are the most frequently researched, the cannabis plant also contains additional therapeutic compounds, including terpenes.

Addressing anxiety is the most commonly cited reason for using medical cannabis. CBD is recognized as an anxiolytic cannabis compound, while THC can help relieve anxiety at low doses but cause anxiety at higher doses or if administered without CBD.

THC and anxiety

A double-blind, crossover study found that a higher vaped or smoked THC dose of 10 or 25 mg significantly increased feelings of “heart racing,” and the 25 mg dose significantly increased feeling anxious or nervous compared to placebo. Subjects were healthy adults who had used cannabis throughout their lifetimes but not within one month of the study.

Data pooled from four double-blind, placebo-controlled (DBPC) studies found that feelings of heart racing, anxiety, nervousness, or restlessness increased in a dose-dependent manner, especially in females. Doses included 5-10 mg or 20-25 mg of THC, vaporized or taken orally.

Another DBPC study reported anxiety increased in a dose-dependent manner using 0.015 or 0.03 mg/kg intravenous doses of THC versus placebo. However, another randomized DBPC study found that 10 minutes of smoking a 12.5% THC product found no increase in reported anxiety. Doses of 86 and 73 mg for men and women were achieved, respectively.

CBD and anxiety

CBD appears to modulate various brain systems by impacting serotonergic, endocannabinoid, opioid, and adenosine transmission, promoting hippocampal neurogenesis and synaptic plasticity, and downregulating glial reactivity.

Low to moderate doses are most effective, while higher doses may block anxiolytic effects. A randomized DBPC trial found that a CBD dose of 300 mg significantly reduced ratings of anxiety when given 90 minutes before a simulated public speaking task. Similarly, 300 mg of CBD given to subjects with Parkinson’s 90 minutes prior to public speaking significantly decreased anxiety before, during, and after the speaking event. However, another randomized DBPC found that 150, 300, or 600 mg doses did not affect test anxiety in healthy college students.

In a DBPC trial of 17 teenagers with social anxiety disorder, a daily 300 mg dose of CBD for four weeks significantly reduced anxiety symptoms. Higher doses titrated to up to 800 mg per day significantly reduced anxiety symptoms in a group of 12-25-year-olds with DSM-5 anxiety disorder who had not responded to standard treatment with cognitive behavioral therapy and/or antidepressants. A 50% reduction in symptoms was seen in 40% of subjects over three months.

Randomized double-blind, placebo-controlled trials found that 400-800 mg doses of CBD effectively and significantly decreased general anxiety and drug-cue-induced anxiety in individuals with heroin and cannabis use disorders.

Optimal Takeaways

• THC and CBD are plant cannabinoids that interact with the human endocannabinoid system
• THC may reduce anxiety at low levels but can increase anxiety in a dose-dependent manner unless paired with CBD.
• The anxiety-causing effects of THC may be blunted by long-term use.
• CBD can improve anxiety symptoms in:
• PTSD from non-sexual trauma
• Teens with social anxiety disorder
• Young individuals with treatment-resistant anxiety disorders
• Social or public speaking-induced anxiety
• Chronic dosing appears to be the most effective

Reference

Lichenstein, Sarah D. “THC, CBD, and Anxiety: A review of recent findings on the anxiolytic and anxiogenic effects of cannabis' primary cannabinoids.” Current addiction reports vol. 9,4 (2022): 473-485. doi:10.1007/s40429-022-00450-7