How It Works
Light therapy generally involves full-spectrum bright light exposure directly onto the eyes using a light source, such as a light box or a light visor. With a light box, the patient sits in front of the light while a visor allows for more mobility. Some healthcare providers have light boxes available in their offices, but this necessitates a daily visit to the doctor. There are also companies that rent the equipment. Insurance does not always cover the expenses associated with this type of treatment. Light therapy is used to treat the depressive episodes of bipolar disorder. Therefore, it’s important that a person has anti-manic coverage while undergoing light therapy. A person with bipolar disorder should not undergo light therapy without first discussing it carefully with their physician.
Exposure Amounts
One aspect of whether light therapy will be beneficial depends on proper dosing. The dose is determined by the intensity of the light, the distance a person is from the lightbox, and the duration of light exposure. The majority of light sources provide 10,000 lux. For seasonal affective disorder, the suggested starting dose is 10,000 lux of morning light for 30 minutes daily. For people with bipolar disorder, several different doses have been used in studies. Exposure between 5,000 and 7,000 lux for 15 to 60 minutes is one recommendation for the treatment of bipolar depression. It’s interesting to note that people with rapid cycling bipolar disorder may respond better to midday light, as compared to morning or evening light.
Pros and Cons of Light Therapy
Side Effects
Potential side effects of light therapy include eye-strain, headaches, agitation, and insomnia. Insomnia may be reduced by scheduling the sessions in the morning. Also, the potential side effects may be lessened by using a variation known as dawn simulation, in which the intensity of the light is increased slowly as if the sun were rising. In some cases, symptoms of mania appeared to be initiated by this therapy. In this case, light therapy may need to be temporarily discontinued, or the dose may need to be reduced. In very rare cases, some women reported menstrual irregularities during treatment. It’s important to note that light therapy is a medical treatment. Before undertaking this type of therapy, be sure to discuss it with your healthcare provider to make sure it’s right and safe for you.
