Cannabis-induced psychosis resolved steadily over one month after stopping use | Research

The takeaway

In 56 patients admitted with cannabis-induced psychosis, positive symptoms like hostility and grandiosity dominated the presentation and showed steady improvement over one month after cannabis cessation.

Psychiatrists, emergency medicine providers, and mental health professionals managing cannabis-related psychotic presentations.

56 patients, mean age 22; steady symptom improvement over 1 month after stopping cannabis

What the researchers found

Cannabis-induced psychotic disorder presented primarily with positive symptoms (hostility, excitement, grandiosity) and minimal affective symptoms. Both positive and negative symptoms showed significant improvement after one week in hospital and one month post-discharge with cannabis cessation.

Why it matters

Understanding the symptom profile and recovery trajectory of cannabis-induced psychosis helps clinicians distinguish it from primary psychotic disorders and set appropriate treatment expectations.

The numbers in context

56 male patients, mean age 22.2 years. Predominant positive symptoms: hostility, excitement, grandiosity. Total duration of cannabis use and family history of substance use correlated with severity. Significant symptom improvement at both 1-week and 1-month follow-ups.

How the study worked

Prospective cohort study of 56 male patients admitted with new-onset psychosis and cannabis use at a tertiary care hospital in Kerala, India (January-June 2019). Assessed at admission, 1 week, and 1 month using PANSS and CGI-S.

What this study cannot tell us

All-male sample limits generalizability. Single center in India. No long-term follow-up to assess relapse or transition to primary psychotic disorder. No comparison group of non-cannabis psychosis patients. Relatively small sample.

How to read the evidence

Small prospective cohort without a comparison group. Useful for describing symptom trajectory but limited generalizability.

When this study was published

Published 2023. Data from January-June 2019.

The bigger picture

The distinction between cannabis-induced psychosis and the onset of primary psychotic disorders like schizophrenia remains clinically challenging. Steady improvement after cannabis cessation supports a substance-induced diagnosis, but some patients will later meet criteria for a primary disorder.

Questions still open

What percentage of cannabis-induced psychosis patients later develop a primary psychotic disorder? Are there early markers that distinguish reversible cannabis-induced psychosis from the onset of schizophrenia?

Common questions

Does cannabis-induced psychosis go away?

In this study, yes. Patients who stopped using cannabis showed steady improvement in psychotic symptoms over one month. However, some people who experience cannabis-induced psychosis eventually develop a primary psychotic disorder, and this study did not follow patients long enough to assess that risk.

What does cannabis-induced psychosis look like?

In this Indian sample, the dominant symptoms were hostility, excitement, and grandiosity (positive symptoms) with relatively few mood symptoms. This is somewhat different from primary schizophrenia, which typically shows more negative symptoms early on.

Read the original research

Psychopathology and Pattern of Remission of Cannabis-Induced Psychotic Disorder.

The primary care companion for CNS disorders, 25(2)

View on PubMed ↗Publisher’s paper ↗

Citation

Suresh, P N; Menon, Vikas; Suresh, Rohith; Uvais, N A. (2023). Psychopathology and Pattern of Remission of Cannabis-Induced Psychotic Disorder.. The primary care companion for CNS disorders, 25(2). https://doi.org/10.4088/PCC.22m03350