There has definitely been significant improvement with my MS depressions since I first started on the Zoloft and ultimately required 100mg. It is obviously still not all gone as was evidenced two weeks ago when I forgot it for a week but I still only require 25mg. I suspect it is one or both of the following. The first is that I have an MS lesion that is resulting in the depression and as that is healing I am no longer requiring as much Zoloft for treatment. The other is that the Omega-3 in the fish-oil pills that I take in having a positive impact on the depression – normally I wouldn’t suspect that but it is one of the listed benefits. Theories aside I probably will never know what is causing the depression nor what is currently helping.