Compare to the active ingredient in MiraLAX. Polyethylene Glycol 3350 Powder for Solution is used to relieve occasional constipation. An osmotic laxative, it works by holding water in the stool to soften the stool and increases the number of bowel movements. Generally produces a bowel movement in 1 to 3 days. Dissolves in any beverage. Available without a prescription. We believe making smart choices for the people, places, and pets in your life should be easy and affordable. And, having quality you can trust should be a given. Thats why you can count on our promise caring for your everyday in every way. Satisfaction guaranteed Love it or your money back.