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 a high fibre diet or bulk forming laxatives and these are not usually recommended in palliative care.
Developing a regular regime is to be encouraged, and can be essential for those on opioids.
A combination of stimulant laxative with a softening or osmotic agent is a good first choice. Consider dose increases after 24-48hrs if no response.
Many patients become expert at adjusting their own laxatives.
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 and syrup
Onset of action: 10–12 hours
Starting dose: 5mg–20mg nocte
Formulations: Tablets and suppositories
Onset of action: 6–14 hours
Starting dose: 5mg–10mg nocte. Stimulant laxative indicated where other stimulant laxatives have failed
Formulations: Oral Liquid
Softeners
(also stimulant action in higher doses)
Onset of action: 1–3 days
Starting dose: 100mg-200mg bd
Formulations: Capsules and oral solution
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.
The Committee on Safety on Medicines (CSM) has advised that the use of danthron-containing products be restricted to treatment of constipation in terminally ill patients of all ages.
Co-danthrusate (dantron 50mg, docusate 60mg)
Onset of action: 6–12 hours
Starting dose: 1–2 capsules at bedtime
Formulations: Oral solution
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. Ensure patients can manage to drink 1-2 litres daily for effective laxative action.
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 25ml concentrated oral liquid dissolved in 100ml water
Formulations: Macrogol oral powders (brands include Movicol®,
Laxido®, Cosmocol®). Concentrated oral solution (Movicol).
Ready to Take Oral Sachets 25ml (Movicol)
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
Peripherally acting Mu opioid receptor antagonists (PAMORAs)
Opioid receptors are present in the gastrointestinal tract. When opioids bind to these receptors they can disrupt normal gastrointestinal function, resulting in opioid-induced constipation. PAMORAs do not cross the blood brain barrier, so relieve the constipation without preventing the analgesic effect of opioids. Caution is recommended if the blood brain barrier is disturbed eg severe dementia.
Specialist use only recommended.
Onset of action: Can be rapid (within 30min); median time 1–6h
Starting dose:
• Patient weight 38–61kg: 8mg SC on alternate days
• Patient weight 62–114kg: 12mg SC on alternate days
Formulations: Subcutaneous injection
Stop other laxatives until effect known.
Onset of action: Median time 5–21h
Starting dose: 25mg PO once daily
Formulations: Tablet
Onset of action: Median time 5–18h
Starting dose: 200microgram PO once daily
Formulations: Tablet
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 - rectal
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: 128ml enema (standard or long tube)
Onset of action: 15–60 minutes
Starting dose: 5ml enema
Spinal cord compression:
All patients may have impaired/lost perception of the need to defaecate, and will need individual bowel management plan.
If normal sphincter sensation and function is present, titrate laxatives as normal, avoid excessive softening.
Lesion above T12-L1: cauda equina & anal reflex intact; reflex/spastic bowel generally responds to rectal stimulation (suppository, digital).
Lesion below T12-L1: cauda equina involved, no anal reflex; areflexic/flaccid bowel generally needs digital removal of faeces.
If standard measures fail
In patients recognised to have significant and ongoing constipation, specialist review may be necessary for full medication review and titration of laxative above standard doses.
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.