- Abnormal biochemistry (e.g. hypercalcaemia, uraemia or hyponatremia) – treat where appropriate.
- Drugs (e.g. opioids, oral bisphosphonates, metronidazole, anticonvulsants) – Anti-emetics may be necessary for a few days when opioid treatment is initiated. Not all patients require this.
- Exacerbating factors such as severe pain, cough, infection, and anxiety need to be treated.
- Avoid drugs with anticholinergic effects in patients with gastric stasis (e.g. hyoscine, antidepressants, cyclizine).
- Constipation – Prevent and treat aggressively.
- Gastritis – Use a proton pump inhibitor e.g. lansoprazole or ranitidine.
- Chemotherapy induced nausea & vomiting – A short course of 5HT3-receptor antagonists may be appropriate.
- Mechanical bowel obstruction–See Section Intestinal Obstruction
- Raised intracranial pressure – See Chapter: Corticosteroids
- Anxiety: Psychological care with or without benzodiazepines.
- Oropharyngeal thrush: a course of antifungal treatment.
ASSESSMENT AND MANAGEMENT PRINCIPLES
Identify and treat underlying cause
Management plan
- Consider non–pharmacological measures, e.g. advice on posture and diet, acupuncture/acupressure, removal of unpleasant stimuli, complementary therapies, psychological treatments such as anxiety management.
- Ensure the most appropriate anti-emetic see is used regularly, to a maximum dose and for a sustained period of time (e.g. 24hrs). Section: Anti-emetic Medications
- Ensure additional PRN anti-emetics are available
- Remember the oral route is often ineffective when someone has nausea or vomiting in which case alternative route should be considered.
If management is ineffective:
- Reconsider the likely cause(s),
- Review the route of administrations
- Another complementary anti-emetic drug may be added (see second line treatment). For example haloperidol with cyclizine is often effective, especially by continuous subcutaneous infusion.
- NB. Cyclizine and other anticholinergic drugs may antagonise some of the effects of metoclopramide and other prokinetic agents. The combination should therefore be avoided if possible.
- Consider using a Syringe driver: a continuous subcutaneous infusion via a syringe driver/pump may be considered for patients who are vomiting for longer than 24 hours or have nausea unresponsive to appropriate oral anti-emetics or are unable to swallow oral antiemetics. See Chapter: Syringe Driver
