pain after BM?

When we finally found a helpful ped GI, he dx’ed my then-18-mth-old son with retained stool which was contributing to his small, frequent BM’s and horrid intestinal cramping and gas. (Before we learned of my son’s MSPI at 7.5 mths, he had stopped pooping on his own at about 6 weeks old and after that would only have diarrhea immediately after we gave him a suppository. So his poor system had been messed up for a long time!) The Ped GI told us to give him Miralax and explained that Miralax goes through the system untouched until it gets into the lower intestines(?) rectum (?) – I don’t remember which – where the Miralax draws moisture into the stool which causes the muscles to feel the urge to expel the stool. He explained that once the rectum muscles have been stretched out by repeated constipation or not used properly due to so much diarrhea, it takes the muscles a long time to get working properly. He indicated for us that it might even be a year or more before his poops would come out easily and “normally”. He said that, in general, he doesn’t purposely try to wean toddlers off from Miralax until after they are potty trained and he said that Miralax doesn’t cause dependency issues. HTH.