The first investigation on the possible antipsychotic effects in humans was done in a schizophrenic patient who had significant hormonal side effects during treatment with a typical antipsychotic (Zuardi et al. 1995).  At the end of the study the videotapes were analysed blindly and in a random sequence by another psychiatrist. Symptoms decreased after CBD treatment and there was a trend for worsening of the symptoms after drug withdrawal. Additional Studies: