Results From A Systematic Review

A systematic review by Australian researchers of medicinal cannabis in the management of anxiety disorders indicates it could be a useful tool.

Anxiety occurs in various forms and intensities, everything from being mildly unpleasant to debilitating. It’s one of the most common and disabling mental health conditions worldwide. According to the Australian Bureau of Statistics, anxiety was the most common mental health disorder among Australians in 2023.

While many treatments exist such as benzodiazepines, antidepressants and cognitive behavioural therapies, they all have their issues and don’t work for everyone. Some individuals are seeking alternatives to standard therapies, including medicinal cannabis.

A study by researchers from various institutions in Western Australia set about carrying out a systematic review of a wide range of cannabis-based preparations and interventions for anxiety-related disorders.

They examined fifty-seven studies that met their inclusion criteria. While a high risk of bias was found in many due to inadequate reporting, among the 13 highest-quality studies, 70% reported a positive improvement for disorders including generalised anxiety disorder (GAD), social anxiety disorder (SAD), and post-traumatic stress disorder (PTSD).

However, 30% of those studies reported a negative result for conditions such as obsessive-compulsive disorder (OCD), trichotillomania (a hair-pulling disorder), test anxiety and SAD.

Of all studies including the lower quality research, more than 90% reported positive outcomes associated with cannabidiol (CBD) and tetrahydrocannabinol (THC)-based cannabis. But more than half (53%) left out or included self-reported data on either form and/or dosage.

The most common method of administration was oral (45 studies, 79%), and 25 of the studies (44%) investigated non-pharmaceutical, self-reported dispensary grade cannabis.

53% of all the studies reported adverse events, the most common being dry mouth (33%), fatigue (18%), somnolence/drowsiness/sleepiness (25%), nausea (19%) and headaches (19%).

The researchers concluded:

“Medicinal cannabis demonstrates potential in reducing anxiety symptoms, but the long-term benefits and overall impact on quality of life remain unclear. Further high-quality, longitudinal research with standardised dosing is needed.”

The researchers said given the increase in prescribing medicinal cannabis to treat anxiety that higher quality research is urgently needed to address gaps in knowledge.

The study was published last month in the journal Psychiatry Research.