Practical Aspects of Light Therapy

Practical Aspects of Light Therapy

In general, it is best to begin light therapy with the patient receiving 10,000 lux. Lower intensities are effective but take significantly more time out of each day. It is usually preferable for patients to obtain commercially available fixtures. Attempts by patients to construct their own fixtures may result in fixtures that put out the wrong amount of light or are electrically unsafe. Commercially available fixtures have additional advantages, such as special ballasts that minimize flicker and features that minimize the transmission of UV rays. Some patients have found a portable head-mounted light device to be useful, but controlled trials demonstrating clear efficacy are still needed (Rosenthal 1998).

Duration of treatment, like dosage of an antidepressant medication, may need to be adjusted according to the needs of the individual patient, the time of year, and the amount of ambient light.

These factors are best considered collaboratively with the patient, who gradually becomes more educated as to his or her need for light. Thirty minutes is frequently a good duration to start with—enough to induce some antidepressant response but not so much as to cause side effects. Although some patients may experience an immediate beneficial effect of light, either activation or a lessening of anxiety, most patients take 2-4 days to register a sustained antidepressant response (Rosenthal et al. 1984). The response to light may be manifested over several weeks (Bauer et al. 1994; Eastman et al. 1998), and a lack of response within the first week cannot be taken as a definitive indication that a patient will not derive any benefit from light over the long run. Light treatments can be administered in divided doses, and some patients report this to be more effective and convenient than when treatment is consolidated in a single block at one time of day.

Light Therapy
Introduction
Diagnostic Indications and Contraindications

• Indications
  
• Contraindications to Light Therapy
  Evidence for Efficacy
  
• Acute-Phase Treatment
  
• Maintenance/Continuation Therapy
  Formal Aspects of Light Therapy
  Novel Treatment Devices