The British Journal of Psychiatry 152: 453-459 (1988)
© 1988 The Royal College of Psychiatrists
Biochemical aspects of therapy-resistant depression
BE Leonard
University College, Galway, Republic of Ireland.
Despite the relatively high incidence of therapy-resistant depression,
there is little clinical evidence to suggest that there are significant
biochemical differences between therapy-resistant and therapy- responsive
patients. A major problem for investigators is the lack of an
internationally recognised definition of resistant depression. Also, it is
possible that depressed patients with delusional symptoms or rapidly
cycling affective disorders from subgroups that are more likely to be
resistant to tricyclic antidepressant treatment and are therefore
classified as therapy-resistant. Evidence is presented to show that an
abnormality in serotonergic function may characterise some therapy-
resistant depressed patients.