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Psychotic Illnesses & Marijuana Abuse


Marijuana abuse use appears to be associated with an earlier onset of psychotic illness, according to a meta-analysis. Many individuals who will develop a psychotic illness later in life induce the early onset of the condition by abusing marijuana.

Marijuana Abuse

Marijuana abuse does not apply to individuals who legally use the substance as prescribed by a doctor to treat certain medical conditions. More than 16 million Americans use marijuana on a regular basis, most of them began using marijuana and often times other drugs during their teenage years.

Marijuana Abuse and Mental Health Study

"There is little doubt about the existence of an association between substance use and psychotic illness. National mental health surveys have repeatedly found more substance use, especially cannabis use, among people with a diagnosis of a psychotic disorder." Matthew Large, B.Sc. (Med.), M.B.B.S., F.R.A.N.Z.C.P., of University of New South Wales and Prince of Wales Hospital, New South Wales, Australia, and their colleagues looked at 83 studies that involved eight thousand one hundred and sixty-seven participants. The data indicated that some of the marijuana abusers developed a psychotic disorder almost three years earlier than they would have normally had.


It is still difficult to say what factors will create a psychotic illness in one individual and not in another that had the same predispositions. However, there is no doubt that marijuana and other illegal drugs do bring about a psychotic disorder earlier than normal if a person has the genetic makeup for the illness.