Constipation is common in advanced disease and can cause many distressing symptoms – colicky abdominal pain, anorexia, nausea, vomiting, urinary retention, anxiety and in some elderly patients may cause confusion.
Consider the causes of constipation. While opioids may be the primary cause in palliative patients, other contributing factors could include reduced mobility, dehydration, hypercalcaemia, neurological deficits and drugs such as anti-cholinergics or ondansetron.
Prevention is the key, and the need to treat constipation is usually due to a failure of prevention.
It should be anticipated when patients are taking opioids or anticholinergic drugs and it is imperative in these patients to prescribe prophylactic laxatives. “The hand that charts the morphine, charts the laxatives”.
A rectal examination must be carried out on all patients to decide on appropriate treatment required.
See flowchart: Management of Constipation Associated with Opioid Use.
See Procedure for rectal examination and suppositories
- Bowel Softeners
- oral – docusate sodium (Coloxyl™) tablets, 50 mg and 120 mg tabs – 240 mg BD maximum dose.
- rectal – glycerine suppositories, Microlax™ enemas, oil retention enemas.
- Bowel Stimulants
- oral - bisacodyl (Dulcolax™) tablets 5 mg 1-2 BD, senna tabs 7.5 mg 2-4 tabs daily.
- rectal – bisacodyl suppositories (need to be placed in contact with the bowel mucosa to be effective). Adult dose 10 mg, child dose 5 mg.
- Stimulant/Softener Combinations - commonly used in Palliative Care:
- Laxsol™ 1-2 tabs BD (maximum 3 tablets TDS – unapproved dose).
- Osmotic Laxatives
- Lax-Sachet™ (macrogol and electrolytes) 1 sachet dissolved in 125 ml of water once daily. Particularly useful for faecal impaction – can be up to 8 sachets per day for 1 – 3 days until bowels open and must be consumed within 6 hours. (Cease other laxatives during Lax-Sachet™ treatment for impaction.)
- Lactulose – NOT recommended for palliative care patients as large quantities of oral fluid needed and can cause severe bloating and flatulence.
- Stimulants are contraindicated for patients with complete bowel obstruction.
- Assess bowel action daily and adjust laxatives accordingly.
- Bulking agents and high fibre diets are not well tolerated by terminally ill patients.
- These will not often be required if a good bowel regime has been started. Use suppositories first (1-2 bisacodyl and if very hard 1-2 glycerol). If these are ineffective then try a Fleet mineral oil enema, left overnight if possible.
- "Fleet enema" refers to both sodium phosphate enema and mineral oil retention enema so it is necessary to specify "sodium phosphate" or "mineral oil" at the time of prescribing:
- Fleet sodium phosphate enema can be used once or twice but prolonged use may cause electrolyte imbalance. Care needs to be taken in administration – do not apply too much pressure.
- Fleet mineral oil enema is primarily a stool softener but can be used for high faecal impaction when the rectum is empty.
- If hard stool is filling the rectum, a docusate (Coloxyl™) enema may be used, since its surface wetting action will help to soften the stool (seek advice from the Palliative Care Service).
- See the Management of Constipation Associated with Opioid Use flowchart.
- Lax-Sachets™ are indicated in the management of severe faecal impaction.
- PicoPrep™ (Sodium picosulfate powder for oral solution) may occasionally be required, particularly if patient is unable to tolerate 8 Lax-Sachets™ per day.
- See flowchart: Management of Constipation Associated with Opioid Use.
Topic Code: 4097