High power cannabis linked to schizophrenia, psychosis, etc.

A systematic review has linked High concentration THC cannabis Products with negative mental health results, especially psychosis, schizophrenia and cannabis disorder.

A new systematic review has examined how cannabis products with high levels of Delta-9-Tetrahydrocannabinol (THC) are linked to mental health results. The analysis has revealed that products with high THC concentrations are linked to negative effects on mental health, especially with regard to psychosis, schizophrenia and cannabis consumption disorder (CUD).

The authors warn that existing research has important limits. They underline the need for better designed studies which can provide clearer and more reliable advice for health care providers and the general public. The review was published in Annals of internal medicine.

The survey was led by researchers at the University of Colorado Anschutz medical campus, as well as their employees. They evaluated 99 studies involving 221,097 participants between 1977 and 2023. The selection criteria were deliberately varied, including all the studies that evaluated the links between high -concentration cannabis consumption and mental health results, whether or not the initial purpose of research was to test therapeutic effects.

Definition of high concentration THC

High concentration cannabis products have been defined as having a concentration of THC exceeding 5 mg of THC or 10% THC per portion or products described as a “high -gap”, “shamer” or “dab”. The mental health results of interest included anxiety, depression, psychosis, schizophrenia, CUD and other consumption of substances. The researchers defined the acute effects (within 12 hours), the post-sued (after consistent use for 1 to 2 months) and the long-term effects (after coherent use for> 1 year).

In studies that do not test therapeutic effects, high concentration THC products were associated with psychosis, schizophrenia and cannabis consumption disorders. No therapeutic study has found any favorable effects on psychosis or schizophrenia.

Non -therapeutic studies, 53% have identified unfavorable associations with anxiety and 41% found unfavorable associations with depression. Among therapeutic studies, some have suggested beneficial effects for anxiety (47%) and depression (48%), while others suggested unfavorable effects (24% for anxiety and 30% for depression).

The results reinforce the previous conclusions according to which higher THC concentrations increase the risk of unwanted mental health results; However, they do not meet the final evidence necessary to provide clear advice to patients.

Reference: “Delta-9-Tétrahydrocannabinol with high concentration cannabis products and mental health results” by Thanitsara Rittiphairoj, Louis Leslie, Jean-Pierre Oberste, Tsz Wing Yim, Gregory Tung, Lisa Bero, Paula Riggs, Kent Hutchison, Jonathan Samelet and Tianjing Li, 25 August 2025, Annals of internal medicine.
DOI: 10,7326 / Annals-24-03819

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