Fever after food poisoning: what should you know?

Food poisoning is caused by contaminated food or drink and may inflame the digestive tract. Fever can appear with diarrhoea, abdominal cramps, nausea, vomiting, chills, or weakness. The fever may settle as the illness improves, while bowel changes can take longer to resolve. Symptoms can also have another cause, so note whether pain is localised, whether stool contains blood, and whether others who shared the meal became ill. Antibiotics are not suitable for every foodborne infection.

Take small, frequent sips rather than a large drink after vomiting. Oral rehydration therapy can replace water and salts; follow the preparation instructions exactly. Continue breastfeeding, and return to simple foods as appetite allows. Rest, wash hands with soap, and avoid preparing food for others while diarrhoea continues. Keep a note of urine output and symptoms. IV fluid therapy may be needed when severe vomiting or dehydration prevents drinking, so contact a clinician if oral fluids are failing.

Get urgent care for confusion, fainting, severe or worsening abdominal pain, blood in vomit or stool, a stiff neck, trouble breathing, or inability to keep fluids down. Arrange prompt assessment for persistent fever, very little urine, a dry mouth with marked weakness, or diarrhoea that is worsening. Infants, older adults, pregnant people, and people with weakened immunity should seek advice earlier because fluid loss can become serious.

Ask whether testing is needed, which fluids or medicines are safe, whether anti-diarrhoeal treatment is appropriate, and how to protect household members. Report recent travel, antibiotics, medical conditions, pregnancy, blood in stool, and the timing of the suspected meal.