Laxatives should be prescribed on a regular basis as soon as weak or strong opioids are prescribed (except those with ileostomy or diarrhoea), with full explanation to the patient.
Many ill patients will not tolerate high fibre diet or bulk forming laxatives and these are not usually recommended in palliative care. Many patients become expert at adjusting their own laxatives. However a regular regime will be essential for those on opioids
A combination of stimulant laxative with a softening/ osmotic agent is a good first choice.
25% of patients on oral laxatives may still need rectal measures at times.
Oral preparations
The information below includes commonly used laxatives – higher than licensed doses may be recommended for opioid induced constipation and for more resistant cases (seek specialist advice).
Stimulants
Increase intestinal motility. Often cause abdominal cramp / colic. Do not use if patient has complete bowel obstruction.
Onset of action: 6–12 hours
Starting dose: 15mg OD – BD
Formulations: Tablets, syrup, and granules
Onset of action: 10–12 hours
Starting dose: 5mg–20mg nocte
Formulations: Tablets
Onset of action: 6–14 hours
Starting dose: 5mg–10mg nocte. Stimulant laxative indicated where other stimulant laxatives have failed.
Formulations: Capsules and elixir.
Softeners
(also stimulant action in higher doses)
Onset of action: 1–3 days
Starting dose: 100mg-200mg bd
Formulations: Capsules and elixir
Combined softeners and stimulants
Combines faecal softening and increased intestinal motility. Do not use if patient has complete bowel obstruction.
Dantron stains urine red (warn patient) and can also cause perianal skin irritation, especially in incontinent patients. It may be prudent to avoid dantron-containing products in dying patients or those who are faecally incontinent or have a colostomy.
Co-danthrusate (dantron 50mg, docusate 60mg)
Onset of action: 6–12 hours
Starting dose: 1–2 capsules at bedtime
Formulations: Capsules 50/60
Osmotic agents - oral
Increase the amount of water in the large bowel. Avoid if patient is dehydrated or has electrolyte disturbances. Avoid if patient has complete bowel obstruction.
Macrogol preparations may be preferable to lactulose if additional softener is required.
Up to 8 sachets a day may be used in faecal impaction.
Onset of action: 1–2 days
Starting dose: 1 sachet dissolved in 125ml. Water or Concentrated oral liquid 25mL dissolved in 100ml water
Formulations: Macrogol oral powders (brands include Movicol®, Dulco-balance®, Laxido® , Molaxole®)
Lactulose alone in usual recommended doses is not effective for opioid induced constipation and should not be used in patients with inadequate fluid intake.
Lactulose can cause flatulence and abdominal cramps.
Onset of action: 1–2 days
Starting dose: 15ml bd
Formulations: Solution
Rectal preparations
Stimulants
Local stimulation of intestine. Do not use if patient has complete bowel obstruction.
Onset of action: 20–60 minutes
Starting dose: 10mg suppository
Onset of action: 1–6 hours
Starting dose: 4g suppository
Softeners
Lubricate and soften faeces.
DO NOT USE IN PATIENTS WITH PEANUT ALLERGY
Onset of action: Normally administered at night (retention enema)
Starting dose: 130ml (warm before use)
Onset of action: 15–60 minutes. Normally administered at night (retention enema).
Starting dose: Dose 120mg in 10g pack.
Osmotic agents - oral
Increase the amount of water in the large bowel.
Ensure the patient is hydrated and that recent U and Es have been taken.
Onset of action: 15–60 minutes
Starting dose: 1 enema
Onset of action: 15–60 minutes
Starting dose: 5ml enema
Spinal cord compression:
If normal sphincter sensation and function is present, titrate laxatives as normal, avoid excessive softening.
If normal sphincter sensation and function is absent, bisacodyl suppositories or other rectal interventions should be prescribed, aiming for a planned bowel action every two to three days.
If standard measures fail
In patients recognised to have significant and on going constipation as a result of opioid use despite measures above, specialist advice may be sought regarding the use of drugs such as the Oxycodone/Naloxone combination (Targinact®) and the opioid antagonists methylnaltrexone injection (Relistor®) and oral Naloxegol (Moventig®) .
Disclaimer
This Guide is intended for use by healthcare professionals and the expectation is that they will use clinical judgement, medical, and nursing knowledge in applying the general principles and recommendations contained within. They are not meant to replace the many available texts on the subject of palliative care.
Some of the management strategies describe the use of drugs outside their licensed indications. They are, however, established and accepted good practice. Please refer to the current BNF for further guidance.
While WMPCPS takes every care to compile accurate information , we cannot guarantee its correctness and completeness and it is subject to change. We do not accept responsibility for any loss, damage or expense resulting from the use of this information.