Slowed Intestine Motion. Paralytic ileus is usually a variety of ileus wherever your intestines are struggling to move food items by them. Methadone might make this affliction even worse.​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​�