Acute endocannabinoid modulation in psychosis and cannabis use
Research type
Research Study
Full title
Acute effects of endocannabinoid modulation: a pilot investigation in co-morbid first episode psychosis and cannabis use
IRAS ID
134771
Contact name
Sagnik Bhattacharyya
Contact email
Sponsor organisation
King's College London
Duration of Study in the UK
3 years, 0 months, 1 days
Research summary
Around 50% of patients treated for their 'first-episode psychosis' (FEP) use cannabis regularly at the onset of psychosis. Given the high rate of relapse after treatment of the first episode, it is crucial to identify any modifiable risk factors. Cannabis use is just such a risk factor. A significant proportion of patients continue to use cannabis after experiencing their FEP, despite psychological and pharmacological treatment.
Traditionally, research into psychosis has focused on the neurotransmitters dopamine and glutamate, but growing attention is being paid to the role of the 'endocannabinoid' system. It has been shown that ‘delta-9-tetrahydrocannbinol’- long regarded as the main psychotropic ingredient in cannabis- selectively modulates brain areas know to be affected in psychosis and induces feeling ‘high’, psychotic symptoms and anxiety. Another molecule- cannabidiol (CBD)- has recently been shown to attenuate changes in the same brain areas, reduce psychosis and anxiety symptoms and has been trialled on inpatients with acute psychosis alone. CBD may also have a role in reducing craving in healthy cannabis users.
This is a pilot placebo-controlled investigational study to determine if CBD has any acute effect in modulating the endocannabinoid system and brain areas affected by heavy cannabis use, FEP with cannabis use and FEP without. We also aim to confirm if it affects psychotic symptoms, anxiety or craving. 24 subjects will be recruited into 2 groups- early psychosis with cannabis use and early psychosis without. Subjects will attend on 2 days, 2 weeks apart and swallow either a capsule of placebo or CBD on each day. They will perform established cognitive tasks in an MRI scanner to look for changes in brain activity. They will answer questions about how they are thinking and feeling to monitor psychotic symptoms, anxiety and any cannabis craving and undergo blood tests and urine samples.
REC name
London - Riverside Research Ethics Committee
REC reference
14/LO/1861
Date of REC Opinion
2 Dec 2014
REC opinion
Further Information Favourable Opinion