Serum dopamine-beta-hydroxylase activity in schizophrenia.

On the basis of a report that serum DBH activity was significantly decreased in schizophrenics, we reexamined this relationship. Serum DBH activity was studied in 90 normal controls and 78 schizophrenics. No significant differences were found for the groups as a whole. The incidence of serum DBH activity below the median for normal controls was significantly less in chronic paranoid schizophrenics than in normal controls.