From the Guidelines
To benefit from a light therapy (LT) lamp for Seasonal Affective Disorder (SAD), a person should use it daily for about 20-30 minutes, preferably in the morning within an hour of waking up, with the most recent and highest quality study suggesting its effectiveness as monotherapy or in combination with other treatments for mild to moderate MDD, regardless of seasonal pattern or seasonal component 1.
Key Considerations for Light Therapy
- Position the lamp about 16-24 inches from your face at eye level, allowing the light to reach your eyes indirectly without staring directly at it.
- Consistency is key, so establish a regular routine.
- Most effective SAD lamps provide 10,000 lux of light, which mimics natural outdoor light.
- While using the lamp, you can engage in normal activities like reading, eating breakfast, or working at a computer.
- For best results, begin light therapy in early fall before symptoms typically start and continue through winter.
- The lamp works by suppressing melatonin production and regulating your circadian rhythm, which helps alleviate symptoms of seasonal depression by compensating for reduced natural sunlight exposure during darker months.
- Most people notice improvements within a few days to two weeks of consistent use.
- If you're taking medications that increase light sensitivity or have eye conditions, consult with a healthcare provider before starting light therapy.
Evidence Supporting Light Therapy
- A systematic review of 1200 patients and 2 RCTs showed similar results in patients without a seasonal element, supporting the use of bright light therapy for persons with mild to moderate MDD, regardless of seasonal pattern or seasonal component 1.
- The benefits of bright light therapy outweighed any potential harm, leading to its recommendation as a treatment option for MDD.
- However, it's essential to note that the evidence had notable limitations, such as lack of blinding, unclear allocation concealment, and small sample size.
From the Research
Benefits of Light Therapy for Seasonal Affective Disorder (SAD)
To benefit from a light therapy (LT) lamp for SAD, a person should:
- Use a light box with an optimum dose of 10,000 lux, as specified in 2
- Expose themselves to the light for 30-60 minutes, as recommended in 2
- Use the light box in the early morning, as morning light has been shown to be more effective in producing complete or almost complete remissions than evening light or placebo, as found in 3
- Continue treatment for at least 3 weeks, as bright light therapy has been shown to have a specific antidepressant effect beyond its placebo effect after this duration, as reported in 3
Potential Side Effects and Considerations
Potential side effects of light therapy include:
- Headache, as reported in 4 and 5
- Nausea, as reported in 4 and 5
- Jumpiness/jitteriness, as reported in 4
- Hyperactivity, as reported in 4
- Emergent hypomania and autonomic hyperactivation, especially during the first few days of treatment, as noted in 5
Treatment Protocols and Devices
Treatment protocols and devices may vary, but:
- The standard of care includes light therapy provided by a light box, as mentioned in 6
- Alternative approaches, such as Bright, whole-ROom, All-Day (BROAD) light therapy, may be feasible and effective, as explored in 6
- The choice of treatment device and protocol should be guided by criteria such as optimum dose, spectrum, exposure duration, and timing, as specified in 2