Cannabis is derived from the cannabis plant (Cannabis sativa). It belongsto the depressant class of drugs and is the most widely used illicit drug in Australia.

The main active ingredient in cannabis is delta-9-tetrahydrocannabinol, commonly known as THC. This is the part of the plant responsible for most of the psychoactive effects or the ‘high’ experienced with cannabis use. There is a wide range of THC potency between cannabis products. Cannabis also contains the non-psychoactive cannabidiol (CBD).