A.W. Zuardi, J.A.S. Crippa, J.E.C. Hallak, F.A. Moreira and F.S. Guimarães (2006). Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug. Brazilian Journal of Medical and Bilogical Research, 39: 421-429.  

Figure 1. Percentage of healthy volunteers who exhibited psychotic-like effects after the ingestion of 0.5 mg/kg D9-tetrahydrocannabinol (D9-THC; lozenges) and a combination of 0.5 mg/kg D9-THC + 1 mg/kg cannabidiol (circles).