Abstract: A pharmaceutical laxative composition in unit dosage form, for peroral administration of picosulphate to a human or other animal subject, comprising a safe and effective amount of picosulphate in a rapidly dissolving matrix; and a proximal colonic delivery carrier which effects release of said picosulphate substantially near the junction between the small intestine and the colon or within the colon of said subject. This invention also involves methods for providing laxation for humans and other animals in need thereof by peroral administration of such compositions.