Brief Psychotic Disorder is a psychosis that has a rapid onset, generally following a major stressor. Its hallmark is emotional turmoil, mood lability, and confusion. The sufferer must have one of the following symptoms: delusions, hallucinations, grossly disorganized or catatonic behavior, or disorganized speech. A brief psychotic episode is time limited, lasting at least a day, but less than a month. As a rule, the quicker the onset, the faster the recovery.