During the delirium and a drug-free control period concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG) and homovanillic acid (HVA) in CSF, activity of dopamine-beta-hydroxylase (DBH), and urinary excretion of norepinephrine, epinephrine, and dopamine (DA) were measured in eight male patients. There were some indications for an increase of noradrenergic activity in the central nervous system.