Wake therapy is a form of sleep deprivation used as a treatment for depression. The subject stays awake all night, or is woken at 1AM and stays awake all morning, and the next full day. While sleepy, patients find that their depression vanishes, until they sleep again. Combining this with bright light therapy make the beneficial effects last longer than one day. Partial sleep deprivation in the second half of the night may be as effective as an all night sleep deprivation session. 
Wake Therapy is a therapy that falls under Chronotherapeutics. Chronotherapy (treatment scheduling) is processes that manipulate biological rhythms and sleep that can help to improve affective disorders quickly.
Wake Therapy is beneficial for those experiencing major depression along with unipolar, bipolar, and melancholic types of depression. Wake Therapy is best used to jump start the affects of the use of an antidepressant. Wake Therapy is the use of prolonged times of wakefulness, along with periods of recovering sleep. It is a fast way to improve symptoms of depression. This therapy is best used with other Chronotherapeutic techniques. After months of use of this therapy and other therapies, it can be quite effective to help prevent and relapse of depression.
Wake Therapy involves one to three rounds which consist of complete sleep avoidance for the night and entire day after, then the cycles are separated with nights of recovery sleep (a full nights sleep). The treatment lasts between two to five days depending on the amount of rounds done. Relapse into depression typically occurs immediately after any amount of sleep. The intervention is done in a hospital or sleep center in order to make sure the program is done properly and full effects are established.
- Wirz-Justice, A; Benedetti F; Berger M; Lam RW; Martiny K; Terman M; Wu JC (July 2005). "Chronotherapeutics (light and wake therapy) in affective disorders.". Psychol Med. 35 (7): 939–44. doi:10.1017/S003329170500437X. PMID 16045060.
- Giedke, Henner; Schwärzler, Frank (2002). "Therapeutic use of sleep deprivation in depression". Sleep Medicine Reviews 6 (5): 361–77. doi:10.1053/smrv.2002.0235. PMID 12531127.
- Martiny, K. (2010). Chronotherapeutics for Affective Disorders: A Clinician’s Manual for Light and Wake Therapy. Acta Psychiatrica Scandinavica, 122(1), 86
- Chicago Psychiatry Associates' Program in Psychiatric Chronotherapy. (n.d.). Chicago Psychiatry Associates' Program in Psychiatric Chronotherapy. Retrieved April 20, 2014, from http://www.chicagochronotherapy.org/waketherapy.html