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Cannabis affects the severity of schizophrenic symptoms: results of a clinical survey

Published online by Cambridge University Press:  09 July 2009

Juan C. Negrete*
Affiliation:
Alcohol and Drug Dependence Unit, Division of Clinical Chemistry, Toxicology Laboratory, Montreal General Hospital, Montreal, Canada
Werner P. Knapp
Affiliation:
Alcohol and Drug Dependence Unit, Division of Clinical Chemistry, Toxicology Laboratory, Montreal General Hospital, Montreal, Canada
Donald E. Douglas
Affiliation:
Alcohol and Drug Dependence Unit, Division of Clinical Chemistry, Toxicology Laboratory, Montreal General Hospital, Montreal, Canada
W. Bruce Smith
Affiliation:
Alcohol and Drug Dependence Unit, Division of Clinical Chemistry, Toxicology Laboratory, Montreal General Hospital, Montreal, Canada
*
1Address for correspondence: Professor J. C. Negrete, Department of Psychiatry, Montreal General Hospital, 1650 Cedar Avenue, Montreal, Canada H3G 1A4.

Synopsis

Data on the history of cannabis use and a spot urine test for cannabinoids were obtained for 137 schizophrenics in treatment. Subjects who were using cannabis during the 6-month observation period presented with a significantly higher degree of delusional and hallucinatory activity than those who did not. Moreover, the group using cannabis made a higher average number of visits to the hospital during the same period. The status of cannabis use appeared to contribute to such variance more than did other relevant factors (age, stage of the illness, amount of medication prescribed, occasional use of other psychoactive substances).

Type
Research Article
Copyright
Copyright © Cambridge University Press 1986

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