My surgeon recommended Miralax to my mother when she had trouble going and passing gas after her surgery.
It worked like a charm and she never had trouble again. But it is NOT immediate. It takes a couple of days to work.
I have used it probably twice a year since my surgery if I feel like I'm getting "backed up" or having a few days where I can't go for whatever reason. It always works for me no trouble. It's the just WAITING for it to work that sucks. LOL (Oh... and the way you have to disolve it in liquid... imho there's no hiding that thickness which grosses me out too. lol)
Good luck!
Wen