I second Gary's comment on pain meds causing constipation. I was taking a stool softner (from Walmart) crushed up and in my peg tube daily. I was also mixing powder fiber stuff (over the counter) daily in my Carnation VHC drink.
Also, talk to your doctor when you are ready to come off the pain meds. I made the mistake of quitting cold turkey and got really sick with cold sweats and shaking.
Tom