Cannabis May Not Be Effective for Insomnia, Study Finds Scientists review clinical trials on medical-grade cannabis and insomnia, concluding that there's insufficient evidence supporting its effectiveness. Better studies are needed to know its benefits and potential risks. Scientists conducted a sweeping analysis of randomized clinical trials looking at medical-grade cannabis for insomnia but found insufficient evidence supporting the idea that it can reliably relieve insomnia. A comprehensive review published in the Cochrane Library analyzed 9 studies involving 537 people between the ages of 18 and 76. The researchers concluded that though it's possible the drug can be a useful sleep aid, better studies are needed to know for sure. Despite its possible benefits, people should discuss the potential benefits and harms with their healthcare provider rather than assuming its effectiveness without proper research.The study's lead author, neurologist Lucia Varela, recommends conducting studies focusing on groups of people especially vulnerable to insomnia and longer follow-up periods to track people's sleep habits. It would also help if future trials used well-defined products and doses, measured sleep in comparable ways, and reported their methods clearly.