Investigating the Role of Diazepam on Brain Function and Chemistry in Psychosis Risk

• Status: Completed
• Trial end date: 2023-03-24
• Target enrollment: 0
• Participant gender: All

Summary

This study will investigate whether a single dose of diazepam (5mg) compared to placebo can modulate brain chemistry (GABA/glutamate levels) and function (blood flow, neural response and connectivity during tasks and at-rest) in 24 individuals at clinical high-risk for psychosis.

• Phase: N/A
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: King's College London
• Collaborators: The Royal Society; Wellcome Trust
• Treatments: Ascorbic Acid; Diazepam

Criteria

Inclusion Criteria:

• Age range 18-40 years

• Capacity to consent to participation in the study

• Inclusion into one of three groups as assessed by the CAARMS: i) genetic vulnerability group, ii) attenuated psychosis group, iii) brief intermittent psychosis symptoms group. This instrument has been modified to additionally allow the scoring of the SIPS v.520. The scoring of the SIPS v.5 is included for comparative purposes and does not constitute inclusion criteria.

• Inclusion based on meeting criteria for "basic symptoms" which are assessed using the Schizophrenia Proneness Instrument (SPI-A)21

Exclusion Criteria:

• History of neurological disorders

• Current exposure to any drug with potential GABAergic or glutamatergic effects other than antipsychotics, mood stabilisers, antidepressants. This includes opiates, psychostimulants, benzodiazepines, atomoxetine, memantine, ketamine, cough medication containing dextromethorphan

• Current or past exposure to any antipsychotic medication

• Pregnancy/breastfeeding

• Contra-indication to MRI scanning (e.g., metal in body, such as pacemakers or implants, claustrophobia)

• IQ < 70 as determined with the shortened version of the Wechsler Adult Intelligence Scale III (WAIS-III)22