Awarded Trial: 08TGF-1257
Secondary Drug Intervention
Duration of Study Period for Each Subject
Pharmacokinetic and drug interaction profile of cannabidiol in combination with certain second generation antipsychotics (serum level; cognitive performance on BACS; side effects).
The goal of this randomized, controlled trial was to determine potential drug-drug-interactions between four frequently used antipsychotics and cannabidiol. Fifty four healthy male and female volunteers, between the ages of 18-45 received placebo or one of the following antipsychotics for ten days: amisulpride (400 mg/day), olanzapine (10 mg/day), quetiapine (300 mg/day) and risperidone (3 mg/day). Baseline serum concentrations of the antipsychotics was established, and 400 mg/day of cannabidiol was added to each volunteer’s regimen on day four of the trial. Serum samples were obtained from all volunteers in order to compare antipsychotic concentrations and cannabidiol concentrations at various time points in the study. Cannabidiol did not significantly affect the serum concentrations of any of the antipsychotics, and could potentially be a safe add-on treatment in schizophrenic patients. These data are being used by Dr. Philip McGuire in a study funded by the Wellcome Trust on cannabidiol in schizophrenia.
F. Markus Leweke
Central Insitute of Mental Health
Ruprecht-Karls-University of Heidelberg
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