Palliative care - constipation

🔍 When to Suspect

Patient, especially on opioids, reports reduced frequency, straining, incomplete evacuation, abdominal pain, bloating, or overflow diarrhoea

From the full topic in The Ocean Library: Palliative care - constipation

🧭 When to suspect

Constipation is one of the most common and distressing symptoms in palliative care, and it should be actively anticipated rather than waited for. NICE notes that it affects nearly all patients receiving strong opioids, so the safest default is to co-prescribe a regular laxative the moment a strong opioid is started. Suspect it on any change from the patient's normal bowel habit – not simply on stool frequency.

The presentation is broad: reduced frequency, straining, hard stool, a sense of incomplete evacuation, abdominal pain or bloating, nausea and anorexia, and – the classic trap – overflow diarrhoea (loose stool leaking past a faecal impaction). The aim of treatment is comfortable evacuation without straining, not a stool of any particular frequency.

The cause is usually multifactorial. Opioids are the leading culprit (causing opioid-induced constipation, OIC), but anticholinergic burden, metabolic derangement (especially hypercalcaemia in malignancy), reduced mobility and intake, and mechanical obstruction from tumour all contribute and are worth untangling.

Category	Common contributors in palliative care
Drugs	Opioids (leading cause); anticholinergics (tricyclics, antimuscarinics, hyoscine); some antiemetics (e.g. cyclizine, ondansetron); iron; diuretics (via dehydration).
Metabolic / disease	Hypercalcaemia, hypokalaemia, hypothyroidism, diabetes (autonomic neuropathy), dehydration.
Mechanical	Intra-abdominal or pelvic tumour, adhesions, anal fissure or haemorrhoids causing painful defaecation.
Neurological	Spinal cord compression, cauda equina, advanced neurological disease.
General / environmental	Reduced mobility, weakness, poor oral and fluid intake, lack of privacy, dependence on others for toileting, unfamiliar setting.

Source: NICE CG140 · Scottish Palliative Care Guidelines

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