Laxal Tab is a laxative used to treat constipation. It may help to increase the number of bowel movements per day and the number of days you have a bowel movement. Laxal is a colonic acidifier that works by increasing stool water content and softening the stool. Laxal is a disaccharide, a sugar molecule composed of 2 smaller sugar molecules bonded together, in this case, fructose and galactose. Laxal is a solid substance that is very soluble in water and has a sweet taste.