My son did not poop today, it's been almost 36 hours without one. He's 9 weeks old, we do a combo of nursing/pumped milk/formula - most of the food he eats is formula but his poops usually are that runny/mustardy poop. Our doctor told us to switch from Similac Advanced to Enfamil Gentlease (which we started yesterday) to help with his gas. How long can he go without a poop before we need to be seriously worried? Thanks!
Re: how long without a poop?