What are the recommended first-line treatments for nausea and vomiting in adults in primary care?

Recommended first-line treatments for nausea and vomiting in adults in primary care involve managing the underlying cause where possible and using anti-emetics tailored to the suspected cause of symptoms.

Simple measures should be tried initially to relieve symptoms, such as providing a calm environment, small palatable meals, and cool fizzy drinks, as these can help reduce nausea and vomiting.

Pharmacological treatment includes prescribing anti-emetics according to their receptor site affinities relevant to the cause of nausea and vomiting. Common first-line anti-emetics include dopamine D2 antagonists such as metoclopramide and domperidone, and antihistamines such as cyclizine. Metoclopramide is effective at moderate doses and also has 5-HT3 receptor antagonism at higher doses, while domperidone has a lower risk of extrapyramidal side effects as it does not cross the blood-brain barrier.

Anti-emetics should be prescribed regularly and as required, with effectiveness reviewed every 24 hours, and continued until symptoms resolve.

In cases related to gastro-oesophageal reflux disease (GORD) or dyspepsia presenting with nausea, empirical full-dose proton pump inhibitor (PPI) therapy for 4 weeks is recommended, with lifestyle advice such as weight reduction, smoking cessation, and avoiding known dietary precipitants.