i am a 52 yo female, having my first colonoscopy. i have had problems with constipation and i also have gastro paresis. According to gastro dr, this is normal. Anyways, i just did round one of the prep about 1.5 hrs ago, and nothing. i have been on milk of magnesia(3tblsp) for the last week.and it didnt help either. Is this normal for the prep NOT to work, or what should i do. Colonoscopy is scheduled for 7:30am. next dose due at 3am... I dont want to go thru this again. what can i do to make sure this works so i dont have to repeat