Fleet Enema is a saline laxative that effectively relieves occasional constipation without causing discomfort or spasms. You may be constipated if you have three or fewer bowel motions per week and your stools are firm, dry, and difficult to pass. Fleet Enema works by increasing the amount of water in the gut, softening the stool and promoting bowel movement. It is good for bowel cleansing prior to having a rectal examination.