Senna (Paediatric)

How it works

Its anthraquinone glycosides are activated by colonic bacteria to stimulate the myenteric plexus, increasing intestinal motility and reducing water absorption to promote a bowel movement.

Prescribing in practice

• It should not be used where intestinal obstruction is suspected, and is generally combined with an osmotic/softening laxative in children rather than used alone for impaction.
• Onset is delayed by several hours, so timing should account for this and avoid disrupting school or sleep.
• Liquid and tablet formulations differ in strength; check the correct preparation and dose against a children's formulary.

Monitoring

Monitor stool frequency and consistency and adjust the dose to maintain soft, regular stools, reviewing the ongoing need as a maintenance regimen is established.

Counselling the patient

• It usually takes several hours to work, so plan the timing accordingly.
• Continue regular maintenance treatment even once stools improve, as advised.
• Encourage adequate fluids and fibre alongside the medicine.

Evidence & guidelines

Stimulant laxatives such as senna feature in NICE guidance on childhood constipation as add-on therapy when an osmotic laxative alone is insufficient.