Lack of balance makes skunk harmful

These discoveries about the link between cannabis and psychosis have been widely reported in the media, often accompanied by warnings that street cannabis has risen in strength in recent years and therefore poses a major health risk to the susceptible minority.

This, however, is too simplistic: the type of cannabis taken is an important factor. Street cannabis has indeed changed over the years. So-called "skunk" does contain higher than normal concentrations of the main psychoactive compound, a molecule called delta-9-tetrahydrocannabinol (THC). What is less well known is that another constituent, cannabidiol (CBD), has been eliminated from skunk through selective breeding to increase the THC content.

The elimination of CBD may play a key role in the development of psychosis. Laboratory studies have shown that pure, synthetic THC causes transient psychosis in 40 to 50 per cent of healthy people. In stark contrast to THC, CBD appears to have an anti-psychotic effect, at least in animals. Studies in humans, though few in number, have produced similar findings.

The elimination of cannabidiol from skunk may play a key role in the development of psychosis

Thanks Sean!