Management of constipation

 

Prevention is more desirable than treatment and steps can be taken for prophylaxis. This

includes;

• Drinking plenty of fluid

• Providing privacy in the bathroom

• Providing a foot stool to help raise the knee

• Prescribing of prophylactic laxatives for patients commencing on opioids

• Advice on increased fibre intake

 

Pharmacological treatment should be adjusted to the needs of the patient and the dose

increased if necessary with the aim of achieving strain free bowel movement every 1-3 days.

According to the Scottish palliative care guidelines for constipation, the following laxatives

are all equally effective and can be divided into classes known as stimulants, osmotic agents, bulking agents and softeners:

 

 

 

 

 

 

 

 

 

Senna

It is a type of stimulant laxative (2 -4 tablets daily)  which take up to 8-12 hours to work. Alternatively bisacodyl (5-10mg daily)  which take between 6-12 hours for effect to occur can be given at bedtime.

Both function by stimulating the myenteric plexus that innervates the smooth muscles to increase contractions for peristalsis. However, if stools become hard then softeners such as docusate sodium (100mg twice a day) should be considered.  

 

• Caution; stiumulant laxatives should not be used in patients with intestinal obstruction due to possible harm. 

• Dose: Prophylactic dose of 15mg is first given at night but if there is no bowel movement after 1-2 days then can increase the dose to 15mg in the morning and 15 mg at bedtime. 

• For relieving constipation then the same dose as above applies (15mg morning and 15mg at bedtime). If constipation continues then the dose can be increased to 22.5mg at bedtime and in the morning

 

 

 

 

 

 

 

Osmotic agents:

Macrogol is an osmotic agent and the mode of action is via absorption of water into the stools to increase the water content so softens stools and cause less straining when bowels are emptied.

•   1-3 sachets daily and if constipation is severe then the dose can be

increased (up to 8 sachets a day) for 3 days.

•   other examples such as lactulose ,mannitol and sorbitol  takes 1-3 days to exert 

effect. 

•  However, this type of laxative requires increased intake of fluid for (2 to 3L daily) best effect and this may not be practical for  patients in palliative care who already experience reduced intake of both food and fluid.