Street Drugs increase risk of Schizophrenia - use of street drugs (marijuana/hash - cannabis, etc.) have been linked with significantly increased probability of developing schizophrenia. Psychiatrists in inner-city areas speak of cannabis being a factor in up to 80 per cent of schizophrenia cases. Researchers in New Zealand found that those who used cannabis by the age of 15 were more than three times (300%) more likely to develop illnesses such as schizophrenia. Other research has backed this up, showing that cannabis use increases the risk of psychosis by up to 700 per cent for heavy users, and that the risk increases in proportion to the amount of cannabis used (smoked or consumed).

Today, there are over 30 published papers linking marijuana to schizophrenia or other mental disorders. The increase in evidence during the past decade could be tied to the increased potency of marijuana. A review by the British Lung Association says that the cannabis available on the streets today is 15 times more powerful than the joints being smoked three decades ago.

The damage that someone does to their brain by smoking marijuana (or taking other street drugs) when they are younger (under the age of 18) may only become evident later in life; between the ages of 19 and 30, when the person develops schizophrenia.

Schizophrenia can sometimes be triggered by heavy use of hallucinogenic drugs, especially LSD; but it appears that one has to have a predisposition towards developing schizophrenia for this to occur. There is also some evidence suggesting that people suffering from schizophrenia but responding to treatment can have an episode as a result of use of LSD. Methamphetamine and PCP also mimic the symptoms of schizophrenia, and can trigger ongoing symptoms of schizophrenia in those who are vulnerable.

Supporting Research (a sample):

See this page for the latest update: Schizophrenia and Marijuana / Cannabis