There is some evidence that light therapy may be useful as a preventive treatment for people with a history of season affectdisorder.
There is some evidence that cognitive behavioral therapy – SAD can be effective in reducing the recurrence and remissions of SAD and has been shown to be sustained at least between a first and second winterseason.
There is limited evidence that St. John’s wort may improve some symptoms of SAD; however, the studies have beensmall.
There is some limited evidence (small trials involving few patients) that suggests melatonin improves sleep in patients with SAD; however, no definite conclusions about its effectiveness can bemade.
At present, vitamin D supplementation by itself is not considered an effective SADtreatment.
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