Phototherapy 

Phototherapy or artificial bright-light treatment, has been used in the management of a number of medical disorders including psoriasis and hyperbilirubinaemia of the newborn. From the point of view of psychiatric treatment, the notion that light might help people with certain psychological symptoms has an ancient lineage. For example, Wehr and Rosenthal cite Aretaeus who suggested in the second century ad that ‘lethargics are to be laid in the light and exposed to the rays of the sun (for the disease is gloom)’. In 1898, a ship's physician named Frederick Cook recorded that the ‘languor’ which affected members of an Antarctic expedition during the winter darkness could be relieved with bright artificial light. The first systematic study of phototherapy as a psychiatric treatment was carried out in 1984 by Rosenthal et al. who used bright artificial light to treat patients with the newly identified syndrome of seasonal affective disorder. Seasonal affective disorder is a recurrent mood disorder in which patients experience regular episodes of depression in autumn and winter with remission in spring and summer. Since then phototherapy has become the mainstay of the treatment of seasonal affective disorder, particularly in patients with atypical depressive features such as hyperphagia and hypersomnia. Phototherapy has also been used as an investigational treatment in other psychiatric disorders but the evidence for its efficacy in these conditions less established.