Might remain active in your system for up to eight hours or more. So by taken at the wrong time you may be doing yourself more harm than good. As was said above, it is best to follow your doctor's orders. Thought you were put on something 3 times a day? The 3rd one was if needed?
From my understanding it is best to take as prescribed. Zoloft my have a time release in it. Talk with your doctor b/4 making that change. Ok? It can really throw you off if you change things up.
Good Luck!