Dude, I tried everything and the only thing that gave me a little bit of relief was taking two colace every day. But still, that relief was minimal. I finally got past the worst of the m/s, laid off the zofran, started eating salads again and my body spent the whole day Saturday eliminating what the zofran held on to for the last 3 months. It was a blessing and a curse. I hope you find the magic cure so you don't have to go through that!
Oh, and btw, my OB swears that it's the prenatals that are causing constipation, not zofran. I don't believe him, but they do make prenatals with stool softeners in them. Might want to look for those and give them a try!