The authors examine the relationship between the age of illness onset and the ability to tolerate a medication-free period in a sample of acutely ill schizophrenic patients. Patients were admitted to an inpatient research unit for the treatment of acute and recurrent psychiatric symptoms. Prior medications were discontinued upon admission to the unit for purposes of clinical research and behavioral assessment uncontaminated by medication side effects. The age of illness onset was significantly and positively correlated with the duration of hospital washout. Furthermore, age of illness onset was significantly correlated with the BPRS total score and the BPRS hostility/suspiciousness factor measured at the end of washout. Our results suggest that early onset schizophrenics deteriorate more rapidly in an acute episode than do their later age of onset counterparts.