Sennosides

Indications

It is used to treat hard stools (constipation).

Pharmacology

Senna glycoside, also known as sennoside or senna, is a medication used to treat constipation and empty the large intestine before surgery. The medication is taken by mouth or via the rectum. It typically begins working in minutes when given by rectum and within twelve hours when given by mouth. It is a weaker laxative than bisacodyl or castor oil.

Sennosides A and B increase intestinal motility through release of active anthraquinones into the colon by colonic bacteria. Purified sennosides (sennosides A and B) are used similarly to senna.

Dosage And Administration

Constipation

  • Adult: 15-30 mg (as total sennosides) 1-2 times daily.
  • Child: 2-6 yr: 3.75-7.5 mg once daily in the morning; 6-12 yr: 7.5-15 mg once daily at night or in the morning; ≥12 yr: 15-30 mg at bedtime.

Bowel evacuation

  • Adult: 105-157.5 mg of sennosides on the day before the procedure. May be given as a liquid preparation.

Contraindications

Nausea or vomiting, undiagnosed abdominal pain, intestinal obstruction.

Side Effects

Mild abdominal discomfort e.g. colic and cramps; diarrhoea, hypokalaemia and atonic non-functioning colon (prolonged use); reversible melanosis coli (chronic use). May colour the urine yellowish-brown at acidic pH or red at alkaline pH.

Pregnancy And Lactation

Sennosides has been assigned to pregnancy category C by the FDA. Animal studies have failed to reveal evidence of teratogenicity. There are no controlled data in human pregnancy. Sennosides should only be given during pregnancy when benefits outweigh risks.

Sennosides is not excreted into human milk. However, Sennosides is a prodrug which is metabolized in vivo to the active sennosides (glucosides of rhein). Rhein is excreted into human milk in very small amounts. No adverse effects have been observed in nursing infants. The American Academy of Pediatrics considers Sennosides to be compatible with breast-feeding.

Precautions And Warnings

Inflammatory bowel disease. Avoid prolonged use.

Therapeutic Class

Osmotic purgatives.

Available Brand Names