(Maple Ridge News p.15 - Saturday, November 4, 2006)
A poll released last month by B.C.'s Centre for Addictions Research showed 53 percent of BC residents have used marijuana at least once. Dr. Bill MacEwan, UBC director of psychiatry, said Canadian clinical evidence as well as those around the world are showing increasing links of pot smoking with psychosis.
Cocaine and marijuana can stimulate dopamine receptors in the brain, leading to mental disorder in the forms of paranoia or hallucinations. In Fraser Health's Early Psychosis Intervention program, at least half of the psychosis patients are substance users and smoke pot.
Dr. MacEwan indicated that chronic long-term smokers (those who smoke at least once a week for more than several months) are at greater risk of psychosis. Psychosis occurs in roughly one in 100 non-drug users, and in those regular pot users, the rate jumps to six to seven times. Not only are the symptoms far worse when the people are smoking marijuana, but the age of onset of psychosis is also lower.