A reader asks:

I have been tracking my migraines for years. I have clusters that go up in the winter and down in the summer. Jan.-Feb.-Mar.-Apr. are the worst, with headaches up to 70% of the days during those months. By May, they drop to 35% of the days. By summer, headaches are 1-4 a month. By the fall, I dread the return of winter and headaches as percentages begin to climb with shortening days. This has gone on for 15 years. Zomig is the only drug that helps but it is expensive. Nortryptiline does not help. Topomax does not help. Can light therapy help me?

Answer:

Good question. Migraines have been related to reduced availability of brain serotonin in winter. The same story holds for winter depression. Many people with winter depression experience headache, which resolves with light therapy. However, others experience emergent headache as a side effect of light therapy, which is no fun. Migraines are often exacerbated by bright light exposure (which is one reason migraine sufferers often retreat to darkened bedrooms), and light therapy for migraine has never been tested in clinical trials. Bottom line: you can certainly test light therapy, but we cannot specifically advise it for this purpose.