Understanding the Mechanism of Action of Drugs Acting on Purgatives

Abstract

Purgatives are termed as laxatives. Purgatives enhance bowel movements to eliminate fecal matter from the body. Bulk-forming laxatives namely psyllium and methyl cellulose show their action by enhancing the volume and water content of the stool and the passage of stool occurs through intestines via peristalsis. Osmotic laxatives such as lactulose and propylene glycol act by drawing water into the intestines. Osmotic laxatives result in constipation. stimulant laxatives such as bisacodyl and senna act by irritating the intestinal lining which results in enhanced peristalsis and increased bowel movements. Emollients or stool softeners namely docusate sodium act by increasing an incorporation of water and fat into the stool, making it softer and easier to pass. An excessive use of laxatives particularly stimulant laxatives may result in dehydration, electrolyte imbalances and damage to the intestines. Finally it is concluded that purgatives play a role regarding management of constipation.