MiraLAX is a polyethylene glycol (PEG 3350) laxative powder made for providing gentle constipation relief. Unlike some laxatives which stimulate the nerves, MiraLAX is a non-stimulant osmotic that works naturally with the water in your body to hydrate, soften, and ease stool through the colon gently. Since going on the market as an OTC laxative in 2007, MiraLAX has been the #1 Physician Recommended OTC brand of laxative. It provides constipation relief without causing harsh side effects like cramping, bloating, sudden urgency, and gas. MiraLAX is made for convenient relief and contains no added taste or grit. fill bottle cap to the indicated line (white section in cap) and pour into 4 to 8 ounces of hot or cold beverage. Mix until the powder is fully dissolved, then drink. MiraLAX generally produces a bowel movement in 1-3 days.