Insufficient evidence to back medical cannabis for insomnia

A new Cochrane review raises doubts about the potential of medical cannabis to alleviate insomnia. The researchers found insufficient evidence to determine if cannabis improves sleep or daytime functioning for those dealing with insomnia, a common sleep disorder affecting quality of life. Insomnia treatment options currently include cognitive behavioral therapy and various medications, but effectiveness varies.

Medical cannabis gained attention as an alternative due to reported benefits in sleep improvement. However, the research on its effectiveness remains uncertain. The review analyzed nine studies involving 537 adults aged 18 to 76, treating them for insomnia. Most focused on primary insomnia, not linked to other health conditions.

Eight trials compared medical cannabis with a placebo, while one compared it with the antidepressant amitriptyline. Results showed little to no clinically meaningful improvement in sleep quality, satisfaction, total sleep time, or daytime functioning compared to placebo. Participants using medical cannabis were more likely to experience mild adverse events like dry mouth and dizziness, but this finding was based on limited studies.

Medical cannabis slightly improved quality of life, but the evidence's certainty was very low, and results were compatible with both slight worsening and large improvement. The overall quality and certainty of the evidence were rated very low to low, primarily due to risk of bias, inconsistent results, and small sample sizes. The studies varied in cannabis product types, limiting comparability, and the longest study followed participants for only 12 weeks, limiting insight into long-term effects.

Additionally, the data were not representative of broader patient groups, being heavily skewed toward younger people and women (72.66% of participants). The authors conclude that the evidence remains weak and uncertain, emphasizing the need for higher-quality research before medical cannabis can be recommended for insomnia. Clinicians and patients should recognize this uncertainty and consider individual circumstances while awaiting better evidence.