Food poisoning from mayonnaise: guidance

Mayonnaise can become unsafe when contaminated or kept at an unsuitable temperature, particularly in dishes prepared ahead of serving. Resulting illness may involve nausea, vomiting, diarrhoea, abdominal pain or fever. The food association is only a clue, not a diagnosis. Tell a clinician about homemade ingredients, storage, serving time, and any other people who ate the same dish.

Take small sips of oral rehydration fluid and pause briefly if vomiting returns, then try again. Rest and choose gentle foods as tolerated. Discard food that may be unsafe without tasting it, clean utensils and surfaces, and wash hands with soap and water. Avoid preparing food for other people while symptoms continue. Ask before using anti-diarrhoeal medicines or antibiotics.

Seek medical advice if symptoms persist, drinking is difficult, or you are worried about dehydration. Get urgent help for bloody or black stools, severe abdominal pain, faintness, confusion, very little urine, repeated vomiting, or ongoing fever. Young children, older adults, pregnant people and those with chronic illness may need earlier assessment.

Ask whether you need testing, how much fluid replacement is suitable for you, and whether your medicines need review. Explain when the mayonnaise was eaten, how it was stored, and the sequence of symptoms.