16.5 Malignant gastrointestinal obstruction

Clinical Features

  • Abdominal distension
  • Vomiting
  • Colic
  • Constipation
  • High pitched bowel sounds

Having ruled out constipation as a cause of symptoms, there are three possible approaches to managing a patient with malignant GI obstruction:

  1. Interventional approach with surgery or stenting for patients with:
    1. Good performance status
    2. Isolated lesions and minimal previous surgery
  2. Oncological intervention for patients with:
    1. Good performance status
    2. No previous chemotherapy treatment or where further effective chemotherapy is available
  3. Medical approach
    1. This approach is likely to be appropriate for the majority of palliative care patients
    2. The traditional 'drip and suck' approach is ineffective in 80% of cases and may be distressing for the patient
    3. Good symptom control can usually be achieved without the use of nasogastric (NG) tubes or intravenous fluids (although a minority of patients do derive symptomatic benefit from an NG tube for refractory or distressing vomiting).

The medical approach to managing GI obstruction differs according to whether the obstruction is partial/sub-acute, functional or complete. The presence or absence of colic is also significant.

If the obstruction is thought to be partial, sub-acute or functional and in the absence of colic, consider a pro-kinetic approach. The obstruction may resolve.

Partial, sub-acute or functional obstruction and no colic:

Metoclopramide 30 - 60mg/24 hours via continuous subcutaneous infusion (CSCI). Sometimes higher doses are required.

Monitor for colic or signs of worsening obstruction. Metoclopramide should be discontinued if these symptoms occur

A cautious trial of faecal softener laxatives e.g. sodium docusate 100mg 8 hourly

Avoid lactulose as it may exacerbate bloating and colic

As a general principle, avoid stimulant laxatives

Corticosteroids may reduce bowel wall oedema

  • A trial of dexamethasone 8 - 16mg given subcutaneously (SC) before midday. The evidence for such an approach is equivocal. The use corticosteroids must be weighed against the risk of side effects and in particular the risk of inducing an improved appetite in a patient who is vomiting.

Complete obstruction or obstruction not resolving

The aim is to optimise control of symptoms such as nausea, vomiting, colic and other abdominal pain. For some patients, vomiting may continue despite optimising antiemetic regimes.

Patients may wish to take small amounts of food and drink, if the nausea is well controlled. Occasional vomits may be an acceptable price to pay for the enjoyment of food; patient's choice and an individualised plan of management are paramount.

General abdominal pain

If clinically appropriate, morphine is the first line SC opioid: administer via continuous subcutaneous infusion (CSCI)


Hyoscine butylbromide: 60 - 120mg/24 hours via CSCI or

Glycopyrronium: 0.4 – 1.2mg/24 hours via CSCI

Nausea & vomiting

Haloperidol and/or cyclizine

  • Haloperidol: 2.5 - 5mg /24 hours via CSCI
  • Cyclizine: 100 - 150mg/24 hours via CSCI (incompatible with hyoscine butylbromide)

Levomepromazine: 6.25mg - 25 mg/24 hours via CSCI as a (broad spectrum antiemetic)

Large volume vomits

Hyoscine butylbromide and glycopyrronium have antisecretory as well as antispasmodic effects.

  • Hyoscine butylbromide; 60-120mg/24 hours via CSCI OR
  • Glycopyrronium; 400micrograms – 1.2mg/24 hours via CSCI

Octreotide, a synthetic analogue of somatostatin, has hormone inhibitory, antisecretory and absorptive effects. It may reduce the volume of vomits in complete bowel obstruction. It should be considered as a 2nd line treatment when the above measures have failed to give adequate symptom control.

  • Octreotide; 500 -1000 micrograms / 24 hours via CSCI. The dose can be reduced by 100 micrograms daily if symptoms are relieved (in order to find lowest effective dose)
  • Please seek specialist advice if considering starting octreotide.

Drainage gastrostomy or nasogastric tubes may be considered, in discussion with the patient, to reduce symptom distress if all else fails.


If thirst is a severe and distressing symptom, consider a trial of intravenous (IV) or subcutaneous (SC) fluids.

Giving IV or SC fluids may increase the volume of vomits and risk increasing symptoms.

Most patients will be comfortable with good oral care including measures such as sucking ice cubes.

Good communication with patients and their family is recommended to clarify the risks and benefits of parenteral hydration.


The addition of an anxiolytic medication e.g. midazolam, to the CSCI regime may become appropriate if the patient is increasingly distressed by their symptoms despite the above measures.

See Care of the dying person for further details


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