sennoside: clinical use

Prescribing considerations

• Exclude obstruction, faecal impaction and an acute abdominal cause before treatment.
• Investigate the cause if laxatives are required regularly or constipation is persistent.
• Avoid prolonged or excessive use because of dependence, impaired colonic function, dehydration and electrolyte disturbance.
• Use particular caution where fluid or electrolyte loss would be hazardous, including renal impairment and frailty.
• Stimulant laxatives do not reduce calorie or nutrient absorption and should not be used for weight loss.

Contraindications and cautions

• Hypersensitivity to the active substance or excipients
• Concurrent use of another laxative with these selected products
• Intestinal obstruction or stenosis, bowel atony or appendicitis
• Inflammatory bowel disease
• Abdominal pain of unknown origin
• Severe dehydration with water and electrolyte depletion
• Pregnancy and lactation for the selected products
• Age restrictions differ between the selected presentations
• Relevant rare hereditary disorders of lactose or galactose handling

Monitoring

• Assess bowel response and investigate persistent symptoms.
• Monitor hydration and consider electrolytes and renal function after excessive or prolonged use or in susceptible patients.
• Review for hypokalaemia where cardiac glycosides, antiarrhythmics, QT-prolonging medicines, diuretics, corticosteroids or liquorice are involved.
• In incontinent adults, minimise prolonged skin contact with faeces.

Clinical pharmacology

Sennosides are colon-activated stimulant laxatives. Colonic bacteria form rhein anthrone, which accelerates transit and increases luminal fluid and electrolytes through antiabsorptive and secretory effects; systemic absorption is limited.

Formulation and product differences

• Both selected products are oral tablets containing standardised senna fruit and lactose monohydrate.
• The adult retail presentation is restricted to adults, while the prescription bulk presentation permits use from 12 years under its product licence.
• The presentations differ in pack type, storage conditions and legal supply status.

Tablet

Route: Oral

Strengths: 7.5 mg