A reader asks:

 Why is it that drug therapy for SAD should not continue year-round, as you say in question #1337? I have heard from a depression expert that one should not go on and off antidepressants, since you risk less efficacy each time you do.


If you are currently treating a depressive episode, or are vulnerable for experiencing one even after you have responded to an antidepressant, it is a big mistake to go on and off meds. That does not apply for Seasonal Affective Disorder (SAD) patients in late spring and summer, and we believe it is wasteful — and bad medical practice — to continue using antidepressants at those times of year. If you have responded to Brand X one winter, it remains likely that you will respond to it again the following winter.


Some doctors prescribe antidepressants year round just in order to maintain compliance — that is, to get the patient into a daily, automatic habit of taking the pills. We give SAD patients more credit than that, to know which half of the year the meds are needed. Some doctors want to avoid any chance of seasonal relapse, which might occur if patients are off meds in the fall. To address this problem, there are studies underway that begin medication in the early fall, while patients are still feeling well, with the aim of preventing onset of the late fall/winter depressive episode. Even then, the medication is discontinued in spring, once the vulnerable period has passed.