Study links cannabis strains with memory impairment

People who smoke potent strains of cannabis that are low in cannabidiol (such as skunk) are putting themselves at far greater risk of acute memory loss than people who smoke other types of the drug, according to new research published in the October issue of the British Journal of Psychiatry . Now the study's authors are calling for cannabis users to be made aware of the risks associated with using some strains of cannabis ' and encouraged to use strains with higher levels of cannabidiol instead. Two major constituents of cannabis are '9-tetrahydrocannabinol (THC) and cannabidiol. THC is the main psychoactive ingredient which makes users feel 'stoned', and produces psychotic-like symptoms such as delusions and paranoia. In contrast, cannabidiol does not induce these symptoms and may counteract the effects of THC. Levels of cannabidiol in cannabis can range from virtually none, to up to 40 per cent. The UCL researchers tested 134 cannabis users aged between 16 and 23 years.