Which dietary instruction is appropriate before a bowel prep for a barium enema?

• A. Avoid red or purple beverages
• B. Take a cathartic the night before
• C. Drink clear liquids the day before to prevent dehydration
• D. Fast completely for 24 hours

Answer: (C)

Before a bowel prep for a barium enema, staying hydrated is essential because the laxatives used to clear the bowel can lead to dehydration. Drinking clear liquids the day before provides hydration while still allowing the bowel to be emptied effectively, since clear liquids are easily absorbed and leave minimal residue that could interfere with imaging. This choice emphasizes safety and the physiological need during prep. Fasting completely isn’t necessary and can worsen dehydration, and while taking a cathartic is part of the prep process, it is not a dietary instruction. Avoiding red or purple beverages may be advised to prevent color interference on images, but the central dietary guidance is to consume clear liquids to maintain hydration.