Bisacodyl

How it works

It stimulates the enteric nerves of the colon to increase peristalsis and also promotes fluid and electrolyte accumulation in the bowel lumen, softening stool and hastening transit.

Prescribing in practice

• Avoid in intestinal obstruction, ileus, acute abdominal conditions and acute inflammatory bowel disease.
• Abdominal cramps and discomfort are common, and prolonged excessive use can lead to fluid and electrolyte disturbance.
• Oral tablets are enteric coated and should not be taken with milk or antacids, which can cause premature dissolution and gastric irritation.

Monitoring

No routine monitoring is needed for short-term use; with prolonged or high-dose use consider fluid balance and electrolytes, particularly potassium.

Counselling the patient

• Tablets usually work overnight, so they are typically taken at bedtime, whereas suppositories act within about an hour.
• Swallow tablets whole without milk or antacids close to the dose, and maintain a good fluid intake.
• Seek advice if you have severe abdominal pain, vomiting or no bowel movement despite treatment.

Evidence & guidelines

Standard stimulant laxative option (NICE CKS constipation).