Cannabis is a commonly used recreational drug, which has
widespread effects within the body. Smoking is the most common form
of administration. The adverse effects of cannabis on behaviour,
cognitive function and psychomotor performance are dose-dependent
and related to task difficulty. Complex tasks such as driving or
flying are particularly sensitive to the performance impairing
effects of cannabis. Chronic cannabis use is associated with a
number of adverse health effects, and there is evidence suggesting
the development of tolerance to chronic use as well as a
well-defined withdrawal syndrome. There is also evidence that the
residual effects of cannabis can last up to 24 hours.
Significantly, the modern dose of cannabis is much more potent than
in the past, when the majority of the research was conducted. As
such, the reported adverse health effects may well be conservative.
Although only a limited number of studies have examined the effects
of cannabis on pilot performance, the results overall have been