What is known

• A systematic review of studies of lactulose as an aperient in a range of populations, including those with terminal illness, showed that lactulose was better than placebo for managing constipation. However in some studies the difference was small. [1]
• A systematic review of docusate in palliative care patients based on small studies which were not of good quality, showed a small trend to increased stool frequency with the use of docusate. The conclusion was that good quality studies are needed to demonstrate the value of this treatment in a palliative care population. [2]
• A prospective open label volunteer study assessing the role of combinations of laxatives in the management of opioid induced constipation provides some support for the common recommendation to use a stimulant and a lubricant laxative together as prophylaxis when prescribing opioids. [3]
• There are small studies of sodium picosulphate [4] and polyethylene glycol (macrogol) [5] in a palliative care population which show promise. Polyethylene glycol has been used in the management of faecal impaction, and appears to be effective [6-7] although these studies were not focused on palliative care patients.

What it means in practice

• Prescribing of laxatives continues to be based on expert opinion. The principles of prescribing laxatives in a palliative care population focus on prevention of constipation. Co-prescription of either a stimulant plus a lubricant laxative, or increasingly, of macrogol, are commonly suggested as best practice for patients on opioids.
• Expert opinion is that fibre and bulk-forming laxatives are associated with problems in palliative care patients, especially if oral intake is reduced. [8]
• Educating patients about the relationship of constipation to opioids, and the need for laxative therapy, is also an essential part of opioid prescribing. [9] 
• Regular assessment of constipation, and of adverse effects of laxative therapy (pain, bloating, flatulence), is an essential part of ongoing care.
• Little is known of the individual variability of response to laxatives. [10]  However it is reasonable to include patients’ own preferences in the choice of laxative.

Finding out more
Guidelines 

• Clinical Knowledge Summaries: Palliative cancer care - constipation

Link to prescribing information
NB Prescribing information may not yet have been updated to include the most recent evidence.

• Online Palliative Medicine Handbook 
  Click on “Notes on Prescribing”
  This prescribing information is from the UK and some medications may not be available in Australia
• Therapeutic Guidelines for Palliative Care
  An Australian source of prescribing information not available directly online through CareSearch, but can be accessed online in most hospitals, or purchased.

Overview article

• Fallon M, O’Neill B. ABC of palliative care: constipation and diarrhoea. BMJ 1997 Nov 15;315(7118):1293-6.

Related CareSearch pages
Opioid
Bowel obstruction
Constipation

References

1. Kot TV, Pettit-Young NA. Lactulose in the management of constipation: a current review. Annals of Pharmacotherapy. 1992 Oct;26(10):1277-82. 
2. Hurdon V, Viola R, Schroder C.  How useful is docusate in patients at risk for constipation? A systematic review of the evidence in the chronically ill. Journal of Pain and Symptom Management. 2000 Feb;19(2):130-6. 
3. Sykes NP. A volunteer model for the comparison of laxatives in opioid-related constipation. Journal of Pain and Symptom Management. 1996 Jun;11(6):363-9.  
4. Twycross RG, McNamara P, Schuijt C, Kamm MA, Jordan C. Sodium picosulfate in opioid-induced constipation: results of an open-label, prospective, dose-ranging study. Palliative Medicine. 2006 Jun;20(4):419-23. 
5. Wirz S, Klaschcik E. Management of constipation in palliative care patients undergoing opioid therapy: is polyethylene glycol an option? American Journal of Hospice and Palliative Care. 2005 Sep-Oct;22(5):375-81.  
6. Culbert P, Gillett H, Ferguson A. Highly effective oral therapy (polyethylene glycol/electrolyte solution) for faecal impaction and severe constipation. Clinical Drug Investigation. 1998 Nov 1;16(5): 355-60. 
7. Ungar A.Movicol in treatment of constipation and faecal impaction. Hospital Medicine. 2000 Jan;61(1):37-40.  
8. Palliative Care Expert Group. Therapeutic Guidelines: Palliative Care. Melbourne; Therapeutic Guidelines Limited: 2005 
9. Berger A M, Parker KP, Young-McCaughan S, Mallory GA, Barsevick AM, Beck SL, et al. Sleep/wake disturbances in people with cancer and their caregivers: state of the science. Oncology Nursing Forum. 2005 Nov 3;32(6):E98-126. 
10. Davis M P. Cancer constipation: are opioids really the culprit? Supportive Care in Cancer. 2008 May;16(5):427-9.  [no abstract available]

This page was created on 20 May 2008 and is due for review in May 2010
Last updated 26 May 2008