Increasing evidence that decompensation into acute psychosis by schizophrenics can often be avoided with active pharmacological and psychosocial intervention at the early signs of relapse has stimulated research into the signs and symptoms prodromal to acute psychosis. In this study, 6-week periods prior to 17 psychotic relapses and to 11 relapses characterized by depression and/or hostility were examined for 23 recent-onset schizophrenic outpatients. These prodromal periods were compared with periods that did not precede relapse for the same patients and for 28 schizophrenic patients who did not relapse. The Brief Psychiatric Rating Scale (BPRS) and the Psychiatric Assessment Scale were used to assess symptomatology. Psychotic relapse was defined as an elevation to severe or extremely severe from non-pathological levels on one or more of the BPRS items: Hallucinations, Unusual Thought Content, and Conceptual Disorganization. Non-psychotic relapses were similarly defined using the Depression and Hostility items of the BPRS. The findings suggest that even slight elevations in delusions, hallucinations, depression, somatic concern, and guilt above the levels usually present for a given patient may presage psychotic relapse during the 6 to 8 weeks prior to its occurrence. When compared to non-prodromal periods of other patients, periods before relapse were found to show significantly higher levels of hostility and grandiosity in addition to higher levels of delusions, hallucinations, and somatic concern. For relapses characterized by depression and hostility, elevations of activation, tension, and depression were found in the prodromal period. (Author/NB)