From Prohibition to Prescription: The Role of Cannabinoids in Sleep

Abstract

Insomnia disorder is the most common sleep disorder and is characterised by self-reported difficulties with falling asleep and/or staying asleep and is associated with significant daytime distress. Despite significant advances in the understanding and treatment of insomnia and the availability of effective treatment options, insomnia management remains suboptimal, posing a significant challenge to public health. Anecdotally, cannabinoids such as cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) are being touted as sleep-promoting drugs. However, evidence for the therapeutic utility of cannabinoids in the treatment of sleep disorders is limited. With increasing consumer interest and uptake of medicinal cannabis globally for the treatment of sleep disorders, it is important that we develop a better understanding of how cannabinoids affect sleep and ‘next day’ function before it becomes routine clinical practice. Therefore, this thesis aims to (1) examine the acute effects of a commonly used ratio of CBD and THC on objective sleep outcomes using polysomnography with high-density EEG in insomnia disorder, (2) determine the ‘next day’ effects of evening administration of CBD and THC on cognitive function, alertness, and driving performance, (3) examine the performance of commonly used point-of collection testing (POCT) devices in detecting individuals who may be under the influence of cannabis. It also provides a comprehensive literature review of the current preclinical and clinical evidence of cannabinoid therapies in the treatment of sleep disorders, and explores the patterns of medicinal cannabis use among a sample of Australians with a self-reported sleep disorder. It is hoped that the work contained in this thesis will advance our understanding of how cannabis impacts sleep and help to guide future research directives and clinical decision making.