This study suggests that patients receiving daily doses of 40 mg of prednisone or its equivalent, are at greater risk for developing steroid psychosis. Psychotic reactions were twice as likely to occur during the first 5 days of treatment as subsequently. Premorbid personality, history of previous psychiatric disorder, and a history of previous steroid psychosis did not clearly increase the patient's risk of developing psychotic reaction during any given course of therapy. Steroid psychoses present as spectrum psychoses with symptoms ranging from affective through schizophreniform to those of an organic brain syndrome. No characteristic stable presentation was observed in these 14 cases reported here. The most prominent symptom constellation to appear some time during the course of the illness consisted of emotional lability, anxiety, distractibility, pressured speech, sensory flooding, insomnia, depression, perplexity, agitation, auditory and visual hallucinations, intermittent memory impairment, mutism, disturbances of body image, delusions, apathy, and hypomania. Phenothiazines administered in average daily doses of 212 mg produced excellent response in all patients studied. Of particular note was the fact that tricyclic antidepressants produced an exacerbation or worsening of the clinical state in all patients to whom they were administered.