Version 1
: Received: 24 April 2024 / Approved: 25 April 2024 / Online: 25 April 2024 (08:51:51 CEST)
How to cite:
Haller, J. Herbal Cannabis and Depression: A Review of Findings Published over the Last Three Years. Preprints2024, 2024041639. https://doi.org/10.20944/preprints202404.1639.v1
Haller, J. Herbal Cannabis and Depression: A Review of Findings Published over the Last Three Years. Preprints 2024, 2024041639. https://doi.org/10.20944/preprints202404.1639.v1
Haller, J. Herbal Cannabis and Depression: A Review of Findings Published over the Last Three Years. Preprints2024, 2024041639. https://doi.org/10.20944/preprints202404.1639.v1
APA Style
Haller, J. (2024). Herbal Cannabis and Depression: A Review of Findings Published over the Last Three Years. Preprints. https://doi.org/10.20944/preprints202404.1639.v1
Chicago/Turabian Style
Haller, J. 2024 "Herbal Cannabis and Depression: A Review of Findings Published over the Last Three Years" Preprints. https://doi.org/10.20944/preprints202404.1639.v1
Abstract
Public perception contrasts scientific findings on the depression-related effects of cannabis. However, earlier studies were performed when cannabis was predominantly illegal, its production was mostly uncontrolled, and the idea of medical cannabis was incipient only. We hypothesized that recent changes in attitudes and legislations may have favorably affected research. In addition, publication bias against cannabis may have also decreased. To investigate this hypothesis, we conducted a systematic review of research studies published over the last three years. We found 156 relevant studies. In most cross-sectional studies, depression was higher in those who consumed cannabis than in those who did not. An increase in cannabis consumption was typically followed by an increase in depression, whereas withdrawal from cannabis ameliorated depression in most cases. Albeit medical cannabis reduced depression in most studies, none of these were placebo controlled. In clinical studies published in the same period, placebo also ameliorated depression and in addition, the average effect size of placebo was larger than the average effect size of medical cannabis. We also investigated the plausibility of the antidepressant effects of cannabis by reviewing molecular and pharmacological studies. Taken together, the reviewed findings do not support the antidepressant effects of herbal cannabis.
Medicine and Pharmacology, Psychiatry and Mental Health
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
