ABSTRACT
This study had been carried out in psychiatric department of Zagazig University Hospital and Al Azazy Mental Hospital with the aim of studying the association between serum testosterone levels and aggression in some psychiatric disorders. 24 schizophrenics and Substance abusing who presented to the outpatient clinic with aggressire behaviour were subjected to the following; DSMII, R and clinical diagnosis, Brown aggressive scale and also measurement of free and total testosterone and sexhormone binding globulin [SHBG] by radioimmuno- assay and Enzyme immuno- assay teahniques. The results showed that substance abusing males had significautly higher serum levels of total and free testosterone than schizophrenics and controls. Also among schizophrenics the serum level of this hormone decreased significantly more with age compared to the other two groups, and correlated negatively with the duration of neuropleptic drug usage. The results also showed that the aggressive behavior of the schizophrenics were significantly lower than that of the drug abusing subjects, however there was no significant correlations between serum testosterone levels and the intenesity of aggression in either the schizophrenics or the substance abusing subjects