The Cannabis Act was introduced to the Canadian House of Commons one year ago, which would legalize the possession and use of marijuana. The Act is expected to become law in July 2018. The medical use of marijuana was the thin edge of the legalization wedge, and the new law is likely to fuel even greater interest in marijuana among patients.
An examination of medical use is limited by the small number of studies of smoked marijuana. Most studies have examined a few of the many cannabinoids found in marijuana, notably tetrahydrocannabinol (THC), which is psychoactive, and cannabidiol (CBD), which is not. Synthetic formulations include oral dronabinol (THC; Marinol), and nabiximols (THC/CBD’ Sativex), which is an oral spray,
The following is a summary of the studies to date.
Epilepsy: A review of 6 randomized controlled trials and 30 observational studies concluded that oral CBD 20 mg/kg was more effective than placebo in reducing seizure frequency >50% (relative risk 1.74) and in achieving freedom from seizures (relative risk 6.17) (Stockings et al. J Neurol Neurosurg Psychiatry 2018; epublished March 6, 2018). Oral CBD may also be effective as adjuvant therapy in treatment-resistant pediatric epilepsy (Devinsky et al. Lancet Neurol 2016;15:270-278).