Bowel Cleansers
Examples
Stimulants
- Senna
- Bisacodyl
- Docusate (also acts as a softener)
- Glycerol
Cleansers
- KleanPrep
- Sodium Picosulphate (Picolax)
Indications
- Constipation
- Prior to certain bowel procedures: radiological imaging, scoping or surgery
- Faecal Impaction
Contraindications
Contraindications
- GI obstruction
- Perforation
- Heart failure
Caution
- Be careful with patients who are more sensitive to shifts in fluid balance (e.g. heart failure, renal impairment and the elderly), ensure patients are kept adequately hydrated as electrolyte disturbances and renal failure due to hypovolaemia may occur.
- Give more than one laxative with extreme caution as this can lead to diarrhoea.
Mechanism
Stimulant laxatives and bowel cleansers work the same way. They work by increasing the volume of electrolytes in the bowel, this draws water into the bowel from the mucosa increasing the volume of fluid in the bowel.
It has also been speculated that stimulant laxatives have an effect of the myenteric plexus causing increased peristalsis.
Administration
Oral (liquid or tablets)
Rectal
Adverse Reactions
- Nausea
- Vomiting
- Abdominal pain / discomfort
- Diarrhoea
- Senna can also cause clinically irrelevant (but concerning looking!) discolouration of urine to a red/brown colour
Interactions
No relevant interactions.
Education
Stimulant laxatives take at least a few hours to work, bowel cleansers kick in much faster. Warn patients that they need to have a bathroom close to hand once they take it, especially rectal suppositories! Most cleaners are given as 2 doses, 8 hours apart, the day before the procedure.
Stimulants may take a few days to have an effect and tend to work well in combination with a softener.
Pharmacokinetics
Nil relevant.
