Macrolax is an iso-osmotic laxative containing macrogol 3350 and electrolytes (1 sachet contains 6.94g). Macrogol 3350 in the intestinal lumen collects a large quantity of water which results softening of fecal mass and stimulating natural peristalsis. Macrogol 3350 is not absorbed from the gut and is expelled from the digestive tract unchanged. The presence of sodium and potassium salts in macrolax helps to maintain the intestinal electrolyte balance.