Bowel Preparation for Colonoscopy: GoLYTELY vs. MiraLAX

MiraLAX — polyethylene glycol (PEG) 3350 without electrolytes — is commonly used for bowel cleansing before colonoscopy. However, it is not FDA approved for this indication; furthermore, it is typically mixed with Gatorade, which makes it hypotonic compared to PEG-based solutions with electrolytes (e.g., GoLYTELY). Data on the efficacy and safety of MiraLAX are mostly anecdotal.

Now, researchers have conducted a randomized, blinded, controlled trial to compare the efficacy and tolerability of MiraLAX with those of GoLYTELY. Adults scheduled for screening colonoscopy received one of the following four bowel preparations, given in split-dose fashion (i.e., half the evening before and half the morning of colonoscopy):

• 4 L of GoLYTELY

• 255 g of Mir…