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Stimulant Laxative

Senna

Brand names: Senokot, Manevac

Senna is a stimulant laxative for the short-term treatment of constipation.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

Directions take preferably at bedtime or as directed by a doctor adults and children 12 years of age or older - starting dosage: 2 tablets once a day, maximum dosage: 4 tablets twice a day children 6 to under 12 years - starting dosage: 1 tablet once a day, maximum dosage: 2 tablets twice a day children 2 to under 6 years - starting dosage: 1/2 tablet once a day, maximum dosage: 1 tablet twice a day children under 2 years - starting dosage: ask a doctor, maximum dosage: ask a doctor

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2023-10-21. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

Its anthraquinone components stimulate colonic motility and secretion, usually producing a bowel movement within about 8-12 hours.

Prescribing in practice

  • Avoid in intestinal obstruction.
  • Use it short-term — prolonged use can lead to dependence and electrolyte disturbance.
  • Address underlying causes, fluid and fibre intake.

Monitoring

Review bowel habit; no routine monitoring.

Counselling the patient

  • It usually works overnight.
  • Drink plenty of fluids.
  • It is not for regular long-term daily use without advice.

Evidence & guidelines

A first-line stimulant laxative for constipation per NICE CKS guidance.

Reference: NICE NG31 Palliative Care — Constipation; SPC Senokot; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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