What should you know about instant food poisoning?

Food poisoning is an illness caused by contaminated food or drink. It can bring nausea, vomiting, diarrhoea, abdominal pain, and fever. Losing fluid through vomiting or diarrhoea can lead to dehydration, with thirst, a dry mouth, dizziness, weakness, or passing less urine. Symptoms can vary in intensity, and a shared meal does not prove which food caused them. Symptoms also have causes other than food poisoning, so the pattern and your health history matter.

Take small, frequent sips of water or oral rehydration solution. If vomiting occurs, pause briefly and restart with tiny sips rather than drinking a large amount at once. When appetite returns, choose simple foods you tolerate and avoid alcohol. Wash hands carefully and do not prepare food for others while unwell. A clinician or pharmacist can advise about medicines; do not use anti-diarrhoeal treatment when there is blood in the stool or significant fever without advice.

Seek urgent care for confusion, fainting, severe dehydration, severe or localised abdominal pain, blood in vomit or stool, repeated vomiting that prevents drinking, or difficulty staying awake. Arrange prompt medical advice for persistent fever, symptoms that are worsening, or illness in a baby, older adult, pregnant person, or someone with a weakened immune system. IV fluid therapy may be needed when oral fluids cannot replace losses.

How can I tell whether I am dehydrated? Is oral rehydration therapy enough for me? Do I need testing or treatment for an infection? When can I safely return to work or prepare food?