Bright light therapy and seasonal affective disorders in clinical practice

Bright light therapy is the treatment of choice for seasonal affective disorder (SAD) which affects 2-3% of the general population, SAD being more common in women. Although the mode of action of bright light therapy is only partially understood, at least 60% of patients respond to treatment, with light and transitory side effects. Apart from SAD, bright light therapy is being investigated for other psychiatric disorders such as subsyndromal SAD, seasonal bulimia and premenstrual dysphoric disorder. Treatment modalities and the practical aspects of bright light therapy for seasonal affective disorder are reviewed in this article.