Bright light therapy can ease bipolar depression in some patients, according to a study published in the journal Bipolar Disorders.
Researchers from the University of Pittsburgh School of Medicine's Western Psychiatric Institute and Clinic studied nine women with bipolar disorder to examine the effects of light therapy in the morning or at midday on mood symptoms.
“There are limited effective treatments for the depressive phase of bipolar disorder,” said Dorothy Sit, M.D., assistant professor of psychiatry and the study's first author. “While there are treatments that are effective for mania, the major problem is the depression, which can linger so long that it never really goes away.”
In this study, women with bipolar depression were given light boxes and instructed on how to use them at home. The women used the light boxes daily for two-week stretches of 15, 30 and 45 minutes. Some patients responded extremely well to the light therapy, and their symptoms of depression disappeared. The responders to light therapy stayed on the light therapy for an additional three or four months. Four patients received morning light, and five used their light boxes at midday. Participants also continued to take their prescribed medications throughout the study period.
“Three of the women who received morning light initially developed what we call a mixed state, with symptoms of depression and mania that occur all at once – racing thoughts, irritability, sleeplessness, anxiety and low mood,” said Dr. Sit. “But when another group began with midday light therapy, we found a much more stable response.”