A reader asks:

I go to bed at 10 PM and wake up at 9 AM every day, and I have to take a nap for 30 – 45 minutes at 2 PM. (I do not have Seasonal Affective Disorder [SAD] .) I wake up as much as three times a night, but I have trained myself to go back to sleep within ten minutes.  It seems to me that I am sleeping soundly. I have also been wearing blue-blocking glasses in the evening. This helps me wind down and get to bed on time. Otherwise, I tend to go to bed at 12:30 AM or later. Nothing has enabled me to sleep less, however. Your dawn simulator sounds perfect for me. I would also like to know if I should buy your recommended light box now. Or does it make sense to wait and see if the dawn simulator solves the problem before seeking relief with another product?

Answer:

There could be many factors underlying your current need for long sleep and daytime napping. They include nonseasonal depression (which, like SAD, can treated with light therapy). It matters that you have found blue-blockers helpful. We’re glad you’re having success with that method.

Looking into morning light therapy as the next step is a good idea. We suggest that you begin with standard bright light therapy rather than dawn simulation. (You can move on to dawn simulation if bright-light treatment works.) Begin by waking to an alarm clock about 15 minutes before your current 9 AM wake-up time. Raise your light settings in 30-minute stages to make sure you easily take these first trial doses. If you feel more awake as a result, and if waking up for each session gets easier over several days, gradually move the light therapy period earlier by 15 minutes every few days. As this routine gets more familiar, you may get the feeling that you could do better by taking in more light. If that’s the case, try adjusting your settings to 45 minutes instead of 30. Maybe the need for napping will go away once you start morning light therapy. Treat your afternoon tiredness as less troubling than your sleep patterns at night. In giving this advice, we assume that you are not taking antidepressant or mood-stabilizing drugs. If you are taking a medication, first get your doctor’s OK and be sure to keep your doctor in the loop about the treatments.