This advice is sourced from Dr Ros Taylor, a senior palliative physician
Q. How should I best manage constipation in patients with advancing illness?
The majority of patients with palliative illness complain of constipation. This is usually due to a combination of medication, reduced hydration and poor mobility. In advanced illness it may be due to something pressing on or blocking the bowel e.g. peritoneal metastases or ascites.
Before prescribing laxatives for constipation you should:
- Consider bowel obstruction
- Review medications to see if any of these contribute to constipation and can be stopped/reduced (e.g. anticholinergics, opioid analgesics, iron, diuretics)
- Discuss diet and fluid intake
- Consider blood tests e.g. U&Es (to assess hydration), Ca2+ and TFTs (to exclude contributing factors)
- Ask if there are any barriers to defaecation e.g. privacy, anal pain from fissures/haemorrhoids
I always ask my patients if a particular type of laxative or food has been effective for them previously as this influences my management.
My approach to treatment is:
- For people who I start on opiates (which slow gut transit) I always prescribe a stimulant laxative (e.g. senna or sodium picosulphate) to prevent constipation. The dose may need titrating as opioid dose increase
- I use a single laxative and increase the dose as needed up to the maximum before trying a second medicine
- For people who have hard stools I advise drinking more fluid and adding in a softener such as Laxido/Movicol and possibly suppositories (e.g. bisacodyl to stimulate and glycerine to soften). The blunt end of the suppository should be inserted first
- Many people struggle with the volume needed for Laxido/Movicol to work effectively, especially if they have nausea
- For people who are struggling to drink much fluid I often increase the background laxative dose
- If the patient develops crampy abdominal pain I reduce the dose of the stimulant laxative and again consider if there is a physical obstruction
- Suspect overflow incontinence if there is a possibility of faecal impaction. A rectal examination and possibly an abdominal X-ray will help to diagnose this
Prescribing tips:
- In my palliative practice the initial treatment approach for patients with constipation is sodium picosulfate liquid starting at 5 mgs per 5 mls and increasing to a maximum of 15 mgs (15 mls) daily
- Naloxegol and Naldemedine reverse the bowel side effects of opiates but retains the pain relief and are useful for severe constipation related to opioid painkillers
- Prucalopride 1-2 mg once a day is also an option for very resistant constipation/gastroparesis
- Lactulose is commonly prescribed but can cause excessive bloating and wind in some patients. It is useful in hepatic encephalopathy