Fleet Saline Enema – Fast Relief for Occasional Constipation, 4.5 oz Get gentle, reliable relief in minutes with Fleet Saline Enema. This ready-to-use, single-dose enema provides fast-acting relief from occasional constipation. Designed with a soft, pre-lubricated Comfortip for easy and comfortable insertion, Fleet's saline laxative works naturally by drawing water into the colon to soften stool and trigger a bowel movement. No preparation needed – simply use and go.