Dophilus

My 4.5-week-old son has really bad colic. At first I used Infacol, and after tips from people last Friday I switched to Dophilus. I don't really feel like it's working because I notice no change at all. Does anyone have tips on what might help, or does anyone know from experience that it takes a while for the Dophilus to start working? It's so sad because then he's truly inconsolable