Bright light therapy (also known as phototherapy) is a treatment option for people who suffer from seasonal affective disorder or SAD. People with SAD typically experience depressive symptoms during the fall and winter months when there is less sunlight, which can lead to feelings of sadness, fatigue and irritability.
Bright Light Therapy involves sitting in front of a special type of bright light called full spectrum light that mimics natural outdoor light. The intensity and duration of exposure varies depending on diagnosis and severity; however, it has been shown to be an effective treatment for those with mild depression even if they do not have SAD.
What is Light Therapy?
Classically referred to as heliotherapy, light therapy consists of either exposure to daylight or another similar form of light as a seasonal affective disorder (SAD) remedy, or exposure of the skin to particular light wavelengths using polychromatic polarized light to relieve a skin disease.
It is used as a therapy for seasonal affective disorder in the wintertime and circadian rhythm disorders, such as delayed sleep disorder. This article contains what light therapy is, how it is applied, its side effects, etc.
It is known that taking natural daylight, especially in the morning hours, positively and uplifts mood. Bright light therapy can also be used for this purpose. Although observations related to this have been known for nearly a century, it has become a systematic treatment practice for the last 20 years. The devices used for this treatment are now portable and filter UV light. Studies show that early morning bright light therapy leads to mood development and, consequently, to depressive symptoms, it has a regulating effect on circadian rhythm, and it shows that antidepressant drugs increase their effects and improve sleep quality.
Is phototherapy safe?
Yes, in fact it is actually safer than being in the sun.
Phototherapy uses a narrow spectrum of UVA and UVB light delivered by a machine which exposes cells to up to 10-100x their normal dose of sunlight.
Compared to unprotected sun exposure, phototherapy has a better safety profile since it targets specific wavelengths which are more effective at treating skin conditions like psoriasis.
How Does Bright Light Therapy (Phototherapy) Work?
Especially in seasonal depression, it has been determined that its efficacy may be related to its effect on biological rhythms and its effect may occur through monoaminergic and melatonergic mechanisms.
In major depression, there is a change in circadian rhythm. This is more of a phase delay. Clinical and epidemiological studies have shown that the frequency of depression is higher in individuals with phase delay. This phase change in depression is also blamed for some depressive symptoms.
Melatonin is a neuroendocrinal substance that plays an important role in circadian rhythm. Its release increases at night and in the dark; decreases in daytime and light. Melatonin is a hormone that can cause depression. Suppressing melatonin release with bright light leads to an antidepressant effect.
How Is It Applied?
Especially in the early morning hours, 10,000 lux half-hour or 2,500 lux 2-hour applications are the most common applications and the effectiveness has been shown to be higher at these doses and durations. The application period is 1 week. During the application process, the person does not look directly at the light source and sits on his side. There must be at least 1-meter distance between the device and the person.
Are There Any Side Effects?
It has no serious side effects. However, it has been reported that when used at high doses and durations in mood patients, it may cause manic switches. It has been suggested that it may cause nausea and headache due to the increase in the dose or the prolongation of the duration. No harmful effects on eyes have been observed. Conscious and controlled use at appropriate doses and times is important for all these side effects.
In What Situations Can It Be Used?
This method of treatment is used in seasonal mood disorders along with drug therapy. It has been used especially in cases of depression that occur depending on the season. It was later found to be effective in non-seasonal depression situations. In addition, it can be successfully applied to pregnant women who have sleep disorders due to chronic fatigue syndrome, changing working hours or jet lag, and who cannot be treated with medication.
Last Updated on December 3, 2021 by Lucas Berg