Bisacodyl, commonly known by the brand name Dulcolax, is a stimulant laxative widely used for short-term relief of constipation and bowel preparation before procedures. It works by directly stimulating the enteric nerves in the colon, increasing peristalsis, and promoting bowel evacuation.

Mechanism of Action:
Bisacodyl acts primarily on the large intestine. It stimulates intestinal smooth muscle and alters water and electrolyte transport, increasing fluid accumulation in the bowel and triggering defecation. The result is a bowel movement typically within 6–12 hours orally or within 15–60 minutes when given rectally.

Dosage Forms and Dosing:
Bisacodyl is available as oral tablets (5 mg) and rectal suppositories (10 mg). Typical adult dosing is 5–15 mg by mouth once daily or 10 mg rectally as needed. It’s often used for acute constipation, bowel prep, or to prevent straining in specific medical situations.

Adverse Effects:
Common side effects include abdominal cramping, diarrhea, and nausea. Chronic or excessive use may lead to electrolyte imbalances, dehydration, and laxative dependence.

Drug Interactions and Monitoring:
Concurrent use with antacids, proton pump inhibitors, or milk may cause premature dissolution of enteric-coated tablets, leading to gastric irritation. Monitoring for bowel regularity, hydration status, and signs of electrolyte imbalance is important—especially in elderly or debilitated patients.

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