1. Management of constipation – the evidence
The Royal Society of Medicine
Palliative Care Conference
Scarborough 2006
Dr Iain Lawrie
Specialist Registrar in Palliative Medicine
The Yorkshire Deanery

3. Constipation through the ages
What is constipation?
The problem - the general population
- in palliative care
Management options & evidence

4. Historical perspectives
Use of purgatives, enemas & emetics since ancient times
Bile (one of the “humors”)
Prophylactic as well as treatment
17th century “enema craze”
Modern, Western diet
Continuing misconceptions

5. What is constipation? Many definitions, no consensus. e.g.
Dissatisfaction with frequency of bowel movements
Hard stool consistency
Discomfort on defecation / straining
Sensation of incomplete evacuation
Less than 3 bowel movements per week
Less than 35g of stool per day
Stool water weight less than 70%
GITT longer than 5 days

6. The general population
Prevalence of 10%
1/3 of the populations of Western industrialised suffers occasionally
More common in women and with ageing

7. Palliative care patients
Common
Distress levels rival that of pain
50% of hospice admissions report constipation (likely an underestimate)
85% of patients taking opioids require laxatives

8. Management strategies
Basic measures
exercise, fibre, fluids
Laxatives
Bulk-forming
Osmotic
Stimulant
Softeners
others

9. Bulk-forming laxatives
Cannot be broken down (minimal absorption)
Mostly natural or synthetic polysaccharides
Absorb water in the intestine
Not recommended in palliative care
Examples: ispaghula husk, methylcellulose, sterculia, bran

10. Level II evidence, Grade B
Ispaghula husk
n Freq. Consist. Transit Time Subj.
Cheskin et al. (1995)    nc
Ashraf et al. (1995)    nc
Fenn et al. (1986)   nc 
Dettmar & Sykes (1998) nc  nc 
McRorie et al. (1998)   nc nc
Level II evidence, Grade B

11. Level III evidence, Grade C
Methylcellulose
Celevac®
No placebo-controlled trials
Level III evidence, Grade C

12. Level III evidence, Grade C
Bran
Several studies seem to suggest benefits
Added bran …improved stool frequency & consistency (Anderson & Whichelow 1985)
[But] compared to a normal diet, fewer laxatives required, improved frequency & consistency, but more assistance with defecation required (Mantle 1992)
Level III evidence, Grade C

13. Osmotic laxatives
Act by increasing the amount of water in the large bowel
Not (or little) absorbed during intestinal transit
Water in food remains bound & in bowel lumen
Include magnesium salts, saccharines, & macrogols

14. Level III evidence, Grade C
Magnesium salts
Magnesium hydroxide (milk of magnesia)
Compared to a bulk laxative – Mg caused more frequent bowel movements, more normal stool consistency & fewer additional laxatives required
Risk of raised serum Mg levels
Level III evidence, Grade C

15. Level II evidence, Grade B
Saccharines
n Freq. Consist. Comments
Bass & Dennis (1981)   flatulence
Wesselius-De Casparis et al. (1968) (success rate 80% [vs 33%] in
constipated patients)
Sanders (1978)  fewer enemas
reduced flatulence
Level II evidence, Grade B

16. Level I evidence, Grade A
Macrogols
n Freq. Consist. Comments
Andorsky & Goldner (1990)   Minor loose stool & cramp
Attar et al. (1999)  Better tol. than lactulose
Cleveland at al. (2001)  Improved symptom scores
Corazziari et al. (1996)    straining,  laxatives
Corazziari et al. (2000)   %/20% not constipated
DiPalma et al. (2000)    ease of defecation
Freedman et al. (1997) PEG>lactulose>placebo
Chaussade & Minic (2003)    straining
Level I evidence, Grade A

17. Level III evidence, Grade C
Stimulants
Senna, sodium picosulfate, bisocodyl,
No placebo-controlled trials of any quality
Conflicting evidence of combinations vs stimulants alone
Codanthramer similar to senna + lactulose, strong preparation may be better
Level III evidence, Grade C

18. Level III evidence, Grade C
Stool softeners
Docusate sodium, liquid paraffin
Effect is modest at best
Level III evidence, Grade C

19. Others Cisapride – no longer marketed
Colchicine – 3 small studies, unclear efficacy
Misoprostol – 1 small study, unclear efficacy
Erythromycin – 1 small pilot study, possible benefit
Naloxone – some evidence, further studies underway

20. In summary… Fibre – not recommended in palliative care
Stimulants – beneficial
Softeners – possibly beneficial
Osmotics
Lactulose – overrated & causes side effects
Macrogols – laxative of choice in OIC
Prevention is better than cure!

22. References Ashraf W et al. Aliment Pharmacol Ther 1995; 9: 639-47
Andorsky RI, Goldner F. Am J Gastroenterol 1990; 85: 261-5
Ashraf W et al. Aliment Pharmacol Ther 1995; 9:
Attar A et al. Gut 1999; 44:
Bass P, Dennis S. J Clin Gastroenterol 1981; 3: 23-8
Chaussade S, Minic N. Aliment Pharmacol Ther 2003; 17:
Cheskin LJ et al. J Am Geriatr Soc 1995; 43: 666-9
Cleveland MV at al. South Med Assoc J 2001; 94:
Corazziari E et al. Dig Dis Sci 1996; 41:
Corazziari E et al. Gut 2000; 46: 522-6

23. Dettmar PW & Sykes J. Curr Med Res Opin 1998; 14: 227-33
DiPalma JA et al. Am J Gastroenterol 2000; 95:
Fenn GC et al. Br J Clin Pract 1986; 40: 192-7
Freedman MD et al. J Clin Pharmacol 1997; 37: 904-7
McRorie JW et al. Aliment Pharmacol Ther 1998; 12:
Anderson AS, Whichelow MJ. Hum Nutr Appl Nutr 1985; 39: 202-7
Mantle J. Cancer Nursing 1992; 88:15-18
Sanders JF. J Am Geriatr Soc 1978; 26: 236-9
Wesselius-De Casparis A et al. Gut 1968; 9:84-6