Corticosteroids often induce a variety of psychiatric symptoms, such as alterations of mood, neuropsychological deficits and even psychotic states. To date, only a few studies have specifically addressed behaviour as well as cognitive functioning in patients under steroid treatment. Fifty ophthalmologic patients participated in this prospective study. They received methylprednisolone or fluocortolone at doses of 119 +/- 41 mg/day in the beginning and 75 +/- 22 mg after 8 days of treatment. Psychopathology and neuropsychological functioning were examined before and after steroid therapy, mood was self-rated on days 0, 3, 5 and 8. No marked psychopathological abnormalities such as psychosis, dementia or delirious states were observed. However, a significant proportion of patients suffered from an organic mood disorder, 26-34% experienced a hypomanic syndrome, 10-12% a depressive syndrome. Most neuropsychological tests did not reveal significant effects of steroid treatment. Performance of Word Fluency and Trail Making A improved, while the Auditory-Verbal-Learning and the Digit-Symbol showed a worsening. Psychopathological and neuropsychological effects were not significantly correlated.