Light therapy sometimes called phototherapy involves exposing the patient to an artificial light source during winter months to relieve seasonal depression.The light source must be very bright, full spectrum light
· Blood levels of hormone melatonin is high during certain parts of day. This can be reduced by exposure to light
· When bright light is presented, body's internal clock which controls daily rhythm will shift ahead or delayed when stimulated by light.
· This physiological time shift may be basis for therapeutic response.
Process of therapy
· Simply sitting close to light box, with lights on and eyes open.
· Looking at lights is not necessary, can engage in activities like reading, writing.
· Session can last from 15 min to 2 hours, usually one day. Can be split into sessions.
· Sleep maintenance insomnia
· Seasonal depression
· Use of photosensitizing medications
The patient is instructed to sit in front of the light at a distance of about 3 feet, engaging in a variety of other activities, but glancing directly in to the light every few minutes The duration of administration is 1-2 hours