Light therapy treatment uses full-spectrum light (like the sun, but not like most light bulbs) in the treatment of seasonal affective disorder. For some people with bipolar disorder, especially those with a strong seasonal component to their mood swings, light therapy may be an effective treatment, or an add-on treatment, to lessen or end a depressive episode.
Special lamps or light boxes are available and the treatment involves daily exposure to a given dose (typically 10,000 lux) of full spectrum light for a given period of time (between thirty and ninety minutes a day). A lux is a measure of light or illumination, with moonlight equaling 1 lux, an average home between 200–400 lux, and a sunny day between 32,000 and 100,000 lux. Some people find that manipulating the time of day they take their light treatment can also help to regulate sleep. The lamps cost between $150 and $300, and replacement bulbs run around $15.
A common-sense, and cost-effective, approach to light therapy is to get outside on a daily basis and take a walk, or do some other activity, in full sunlight.