Light therapy is a way to treat seasonal affective disorder (SAD) by exposure to artificial light. Seasonal affective disorder is a type of depression that occurs at a certain time each year, usually in the fall or winter.
During light therapy, you sit or work near a device called a light therapy box. The box gives off bright light that mimics natural outdoor light. Light therapy is thought to affect brain chemicals linked to mood, easing SAD symptoms. Using a light therapy box may also help with other types of depression, sleep disorders and some other conditions. Light therapy is also known as bright light therapy or phototherapy.
Why it's done
You may want to try light therapy for a number of reasons:
Light therapy for conditions other than SAD
Light therapy is also used to treat skin conditions such as psoriasis. However, this is different from the type of light therapy used for seasonal affective disorder and the other conditions above. Light therapy for skin disorders uses a lamp that emits ultraviolet (UV) light. This type of light is filtered out in light therapy boxes because it can damage the eyes and skin.
Light therapy is generally safe. Side effects are generally mild and short-lasting when they do occur. They can include:
When side effects do occur, they may go away on their own within a few days of starting light therapy. You also may be able to manage side effects by reducing treatment time, moving farther from your light box, taking breaks during long sessions, or changing the time of day you use light therapy. Talk to your doctor for additional help and advice, or if side effects don't go away or get worse.
When to use caution
Tanning beds: Not an alternative to light therapy
Cautions for bipolar disorder and severe depression
How you prepare
Before starting light therapy, check with your doctor and mental health provider to be sure that light therapy is a good option for you, and to find out whether you need to take any special precautions.
Internet retailers, drugstores and even some hardware stores offer a variety of light therapy boxes. Or your doctor may prescribe a particular light therapy box. In some cases, health insurance companies require a prescription from a doctor to cover the cost of a light therapy box. Talk with your doctor about the best light therapy box for you, and familiarize yourself with the variety of features and options to help ensure that you buy one that is safe and effective for you.
Although it's possible to do light therapy on your own, it's best have the guidance of a doctor or mental health provider. This can help you get the most benefit out of light therapy and minimize possible side effects.
What you can expect
Starting light therapy
Some people experience seasonal affective disorder in the summer. And others who typically have winter depression may notice symptoms during prolonged periods of cloudy or rainy weather during other seasons. You and your doctor can adjust your light box treatment based on the timing and duration of your symptoms.
If you want to try light therapy for nonseasonal depression or another condition, talk to your doctor about how light therapy can be most effective.
During light therapy
Light therapy sessions are generally done each morning after you wake up. Some light therapy boxes, however, are dawn simulators — they turn on in the morning while you're still asleep and gradually get brighter until you wake up.
Three key elements for effective light therapy
Finding time for light therapy
You can set your light box on a table or desk in your home or in your office. That enables you to read, use a computer, write, watch television, talk on the phone or eat while undergoing light therapy. Some light boxes are even available as visors that you can wear, although their effectiveness isn't proven.
Light therapy is often an effective treatment for seasonal affective disorder. You can sometimes engage in routine activities, such as reading, while undergoing light therapy. ...
Light therapy probably won't cure seasonal affective disorder, depression or other conditions. But it may ease symptoms, increase your energy levels and help you feel better about yourself and life.
Light therapy can start to improve symptoms within just a few days. In some cases, though, it can take two or more weeks.
Getting the most out of light therapy
Last Updated: 2010-10-07
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