The recent escalation of cannabis and amphetamine-type stimulant use throughout the world and its association with psychotic symptoms in users has fuelled special concerns.
This review will focus on cannabis and amphetamine-type stimulant because of their high prevalence and will try to differentiate and compare their associated psychotic features.
A systematic literature search was conducted from 1980 to 2015 in the following databases: MEDLINE, PsycINFO, and PubMed. Articles were included if they were highlighting substance-induced psychoses, with particular emphasis on stimulants/amphetamine/methamphetamine and cannabis/marijuana-induced psychoses, schizophrenia-spectrum disorder, or schizophrenia.
There are many differences between these 2 substances regarding source, neurobiological processes, urine screening test, average latency periods before developing psychosis, clinical features as compared with schizophrenia, risk of using drugs and developing psychosis, and drug use and development of schizophrenia.
Our search elicited many studies of 1 substance and its association with psychosis but few comparative studies of this association across substances. Yet, in our opinion these comparisons could shed further insight into the development of psychotic features.
*KSAH-HS, King Abdulaziz Medical City, Riyadh, Saudi Arabia
†Cumming School of Medicine, Calgary, AB, Canada
The authors declare no conflict of interest.
Reprints: Fares F. Alharbi, MBBS, SSC-Psych, Mental Health Department, King Abdulaziz Medical City, P.O. Box 22490, Riyadh 11426, Saudi Arabia (e-mail: email@example.com).