Written question asked by Iris Robinson (Democratic Unionist Party) on Wednesday, 21 January 2004, in the House of Commons. It was due for an answer on Thursday, 29 January 2004. It was answered by Melanie Johnson (Labour) on Thursday, 29 January 2004 on behalf of the Department of Health.

Dept of Health

Question: To ask the Secretary of State for Health, if he will make a statement on the results of recent research into the association between cannabis use and psychosis.

Answer: Mrs. Iris Robinson: To ask the Secretary of State for Health if he will make a statement on the results of recent research into the association between cannabis use and psychosis. [150747] Miss Melanie Johnson: We recognise that a causative link between early cannabis use and later development of schizophrenia is not conclusively proven. However, the recent epidemiological research on the issue of earlier use of cannabis and risk of later development of schizophrenia, `schizophrenic symptoms' and `schizophreniform disorder' has shown a stronger association than was previously evident from published studies. The British Medical Journal editorial accompanying the publication of the key research papers concluded that: "whether the use of cannabis triggers the onset of schizophrenia or depression in otherwise vulnerable people or whether it actually causes these conditions in non- predisposed people is not yet resolved." The Department continues to monitor research in this area and has a range of expert advisors to continue to inform policy.

Secondary information