Well, as happens frequently, I take a lot of Immodium and am plugged up for days. How many days should I get worried and perhaps take a lazative? I think the most I have ever gone is five. I just worry that it hurts my system to be backing up like that... Then it's usually a normal bm followed by more D, then I repeat the cycle. I start getting concerned after a few days of nothing though, (but prefer it over the D by far).