what is the best treatment for seasonal variation in mood/depression?
Hello.  Seasonal Affective Disorder can be treated with the usual anti-depressants that are used for other depressive disorders. Where the usual anti-depressants don't work, thyroid hormones are also known to help. Photo-therapy (light therapy) is also known to be effective, especially with winter onset depression. Psychotherapy can help improve the depression in the long run.  A combination of these methods is usually employed, based on a persons symptoms. The treatment is usually customized for the individual needs.  Hope this helps.  Abhijeet Deshmukh, MD