Treating S.A.D. through Light TherapyWho hasnât felt like staying in bed and hibernating in the depths of winter? If itâs an occasional feeling, no problem, but if itâs chronic, you could have seasonal deficit disorder (SAD). âFirst and foremost itâs important to get a diagnosis from your physician or health care provider, and then you have two options and both have been validated scientifically. Currently light therapy is the primary treatment for SAD but an alternative is using an antidepressant as well,â explains Iris Krawchenko , of Dell Pharmacy. She adds that anti-depressants must be taken all year long, while light therapy is only used seasonally.