Aim: The aim of this review was to survey the available literature on prodromal symptoms of unipolar major depression.
Methods: Both a computerized (Medline) and a manual search of the literature were performed.
Results: In a substantial proportion of patients with depression a prodromal phase can be identified. There is a relationship between residual and prodromal symptomatology (the rollback phenomenon).
Conclusions: Appraisal of prodromal phase of major depression has important implications as to pathophysiological models of disease and relapse prevention. It may allow a staging system of depressive illness that may yield more enduring results in the therapeutic efforts.