Chronobiological Therapy for Mood Disorders

Chronobiological therapies for mood disorders include manipulations of the sleep–wake cycle such as sleep deprivation and sleep phase advance and the controlled exposure to light and darkness. Their antidepressant efficacy can overcome drug resistance and targets the core depressive symptoms including suicide, thus making them treatment options to be tried either alone or as adjunctive treatments combined with common psychopharmacological interventions. The specific pattern of mood change observed with chronobiological therapies is characterized by rapid and sustained effects, when used among themselves or combined with drugs. Effects sizes are the same reported for the most effective psychiatric treatments, but side effects are usually marginal or absent. New treatment protocols are developed to adapt them in different clinical settings. This review deals with the general principles of clinical chronobiology and the latest findings in this rapidly developing field.