Depression is a syndrome that commonly accompanies schizophrenia. The
presence of depressive symptoms in this entity have been recognized an
d described since the era of Kraeplin and Bleuler, but its significanc
e on the prognosis of schizophrenia is still controversial. The sympto
ms that contribute to the diagnosis of a mayor depressive episode are
not exclusive of depression as they can easily be confused with the ne
gative symptoms of schizophrenia, with akinesia or with the prodromic
symptoms of a psychotic relapse. Even though in the last years much at
tention has been paid to the study and treatment of depression in schi
zophrenia; the diagnosis and the treatment of this entity is still unc
ertain.