Forty-Six Cases of Psychosis in Cannabis Abusers Gunila Bernhardson
International Journal of the Addictions 1972 DOI: 10.3109/10826087209026757 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case series (retrospective survey of psychiatric records) Case report Peer reviewed |
|---|---|
| Sample size | 46 |
| Population | Habitual cannabis users treated for psychosis at Swedish psychiatric clinics and mental hospitals, 1966–1970 |
| Topics | Cannabis |
| Citations | 65 |
| Key findings | Among 46 habitual cannabis users treated for psychosis, 24 had episodes generally lasting 1–5 weeks and 22 had a chronic course; in 14 chronic cases an endogenous psychosis appeared to precede drug use. The authors argue the findings support the existence of a cannabis-induced psychosis, while noting that most patients had prior psychoneurotic traits. |
Abstract
Forty-six habitual users of cannabis, who had been treated for psychosis during the years 1966-1970, were reported following an inquiry sent to Swedish psychiatric clinics and mental hospitals. Twenty-four of these cases had had psychotic episodes generally lasting 1-5 weeks, whereas 22 cases were running a chronic course. In 14 chronic cases an endogenous psychosis seemed to have been present before the drug debut. Seven of these showed a marked aggravation of the psychotic symptoms during periods of cannabis abuse. Eight cases of chronic psychosis occurred in earlier nonpsychotic subjects.Thirty cases occurred in formerly nonpsychotic individuals, though 23 of them had shown psychoneurotic traits. In seven of these, relapse into a second psychotic episode occurred following renewed cannabis abuse. The symptomatology reminded one of schizophrenic or manic-depressive endogenous psychoses in most instances, but confusional states were also seen. Evidence supporting the existence of a cannabis-induced psychosis has been discussed.
Comparable studies
Other case reports and case series on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Psychotic Reactions Following Cannabis Use in East Indians Patients at an Indian drug addiction clinic who developed acute cannabis-related psychosis | 1974 | Descriptive report (case series of clinical observations) | n = 200 |
| Psychiatric effects of cannabis use Swedish cases of cannabis psychosis | 1985 | Case series | n = 70 |
| Hallucinogen persisting perception disorder after psilocybin consumption: a case study 18-year-old man with HPPD after mixed psilocybin and cannabis intoxication | 2005 | Case study | n = 1 |
| Cannabis‐induced Koro in Americans American men aged 22-26 with years of cannabis experience who reported negative... | 2001 | Case series | n = 3 |
| “Hallucinations” Following Acute Cannabis Dosing: A Case Report and Comparison to Other Hallucinogenic Drugs Healthy 30-year-old male | 2018 | Case study | n = 1 |
Citations in the library
Cited by 18
- Gone to Pot – A Review of the Association between Cannabis and Psychosis Frontiers in Psychiatry May 22, 2014
- Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases The British Journal of Psychiatry November 30, 2005
- Acute Effects of Drug Abuse in Schizophrenic Patients: Clinical Observations and Patients' Self-reports Schizophrenia Bulletin 1990
- Cannabis use and psychotic disorders: an update Drug and Alcohol Review November 30, 2004
- Daily use of high-potency cannabis is associated with more positive symptoms in first-episode psychosis patients: the EU-GEI case–control study Psychological Medicine March 18, 2020
and 13 more in the library