The Hong Kong government recently announced a legislative amendment on placing cannabidiol (CBD), a cannabis compound, in the same category as heroin and cocaine. Not only trafficking and manufacturing will face imprisonment and fine, possession and consumption will also be criminalised with comparable penalties. Typically, the ∆9-tetrahydrocannabinol (THC) content is used as an index for the potency of cannabis. THC can cause acute impairments in memory and attention and psychotic symptoms among infrequent users. Higher THC content in cannabis indicates higher risk of onset of psychotic disorder and cannabis disorder in long-term users. Meanwhile, CBD does not impair cognitive performance, and has antipsychotic properties and some previous studies suggested the likelihood of high CBD:THC ratio in cannabis protecting against THC-induced adverse effects. Researchers from the King’s College London examined the acute effects of cannabis containing four different CBD:THC ratios (0:1, 1:1, 2:1 and 3:1) on cognitive performance and psychotic symptoms in healthy volunteers. The findings did not support the claim. CBD did not modulate the effects of THC on cognitive, psychotic, subjective, pleasurable, and physiological measures. Even at the doses typically present in recreational and medicinal cannabis, no evidence of CBD protects against the acute adverse effects of cannabis was found. Therefore any political attempts to decriminalise or legalise cannabis use should implement deliberate research on implications and follow-up plans before actual enforcement.

Reference:

Englund A, et al. Neuropsychopharmacology.