Worldwide study investigates the effect of cannabidiol in the treatment and prevention of psychosis

How effective is cannabidiol in the prevention and treatment psychosis? This question is being investigated in a large-scale study by the British University of Oxford. The University Hospital Schleswig-Holstein (UKSH) in Lübeck is one of 35 participating study centres worldwide. A total of 1,000 participants will be taking part who are either at high risk for the disorder, are in the early stages or suffer from a psychosis that does not respond to conventional therapies. The STEP (Stratification & Treatment in Early Psychosis) study will start this year.

Cannabidiol (CBD) is a component of cannabis plants with no intoxicating effect. Other components get removed for the production of the medicine. CBD has so far only been approved as medicine in a few cases in Germany, for example in rare epilepsy diseases.

“There are already study results that indicate that treatment with CBD can be helpful in existing psychoses. Whether it can also contribute to the prevention of psychoses is what this study will investigate for the first time,” says Prof. Dr. Stefan Borgwardt, Director of the Clinic for Psychiatry and Psychotherapy of the Centre for Integrative Psychiatry (ZIP) of the UKSH in Lübeck.

The participants will take cannabidiol or a placebo for 104 weeks in addition to their standard medication. In addition to studying the efficacy of CBD in psychosis, the research team will look for biological clues (i.e., biomarkers) that could indicate the extent to which patients respond individually to the active ingredient – to enable them to receive personalised treatment in the future.

Worldwide, 0.5 per cent of the population suffers from a psychotic disorder whose symptoms include hallucinations and delusions. Currently available antipsychotic drugs can have side effects and are therefore often discontinued by the patients. In addition, the drugs do not work for all patients. This is another reason why new therapeutic approaches are being sought and investigated.

For questions from journalists, please contact: University Hospital Schleswig-Holstein, Campus Lübeck, Centre for Integrative Psychiatry ZIP gGmbH, Prof. Dr. Stefan Borgwardt, Department of Psychiatry and Psychotherapy, Clinic for Psychosomatics and Psychotherapy Tel.: 0451 500-98800,

To access the official press release in German, please visit the website of the UKSH.

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