When should I consider referring a patient with food poisoning to secondary care for further evaluation?

Consider referring a patient with food poisoning to secondary care for further evaluation if they present with any of the following:

• Signs or symptoms suggesting shock, such as poor perfusion or altered consciousness, requiring emergency transfer to secondary care.
• Red flag symptoms or signs indicating a possible alternative serious diagnosis, including high fever (≥38°C in infants under 3 months, ≥39°C in older children), blood and/or mucus in stool, bilious (green) vomiting, severe or localized abdominal pain, abdominal distension or rebound tenderness, altered conscious state, neck stiffness, bulging fontanelle, or non-blanching rash.
• Symptoms suggesting clinical dehydration or high risk of dehydration, especially in vulnerable groups (e.g., infants under 1 year, immunocompromised patients, or those with significant vomiting or diarrhoea).
• Social circumstances that make remote assessment unreliable or where continued healthcare professional involvement is necessary.
• Suspected septicaemia or systemic infection signs such as appearing unwell or dysuria.
• Presence of bile-stained vomit, haematemesis, or abdominal distension suggestive of surgical emergencies.
• Failure to improve after 7 days or uncertainty about the diagnosis.

In these cases, referral ensures timely specialist assessment, appropriate investigations, and management including intravenous fluids or antibiotics if indicated NICE CG84,NICE NG1.